121.
Chandra Sekhar Tiwary Mohamad A Kabbani, Pedro AS Autreto
Ambient solid-state mechano-chemical reactions between functionalized carbon nanotubes Journal Article
In: Nature Communications, vol. 6, pp. 7291, 2015.
@article{Kabbani2015,
title = {Ambient solid-state mechano-chemical reactions between functionalized carbon nanotubes},
author = {Mohamad A Kabbani, Chandra Sekhar Tiwary, Pedro AS Autreto, Gustavo Brunetto, Anirban Som, KR Krishnadas, Sehmus Ozden, Ken P Hackenberg, Yongi Gong, Douglas S Galvao, Robert Vajtai, Ahmad T Kabbani, Thalappil Pradeep, Pulickel M Ajayan},
url = {http://www.nature.com/ncomms/2015/150615/ncomms8291/full/ncomms8291.html},
doi = {10.1038/ncomms8291},
year = {2015},
date = {2015-06-15},
journal = {Nature Communications},
volume = {6},
pages = {7291},
abstract = {Carbon nanotubes can be chemically modified by attaching various functionalities to their surfaces, although harsh chemical treatments can lead to their break-up into graphene nanostructures. On the other hand, direct coupling between functionalities bound on individual nanotubes could lead to, as yet unexplored, spontaneous chemical reactions. Here we report an ambient mechano-chemical reaction between two varieties of nanotubes, carrying predominantly carboxyl and hydroxyl functionalities, respectively, facilitated by simple mechanical grinding of the reactants. The purely solid-state reaction between the chemically differentiated nanotube species produces condensation products and unzipping of nanotubes due to local energy release, as confirmed by spectroscopic measurements, thermal analysis and molecular dynamic simulations.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Carbon nanotubes can be chemically modified by attaching various functionalities to their surfaces, although harsh chemical treatments can lead to their break-up into graphene nanostructures. On the other hand, direct coupling between functionalities bound on individual nanotubes could lead to, as yet unexplored, spontaneous chemical reactions. Here we report an ambient mechano-chemical reaction between two varieties of nanotubes, carrying predominantly carboxyl and hydroxyl functionalities, respectively, facilitated by simple mechanical grinding of the reactants. The purely solid-state reaction between the chemically differentiated nanotube species produces condensation products and unzipping of nanotubes due to local energy release, as confirmed by spectroscopic measurements, thermal analysis and molecular dynamic simulations.
122.
Acrísio L Aguiar Nadia Ferreira Andrade, Yoong Ahm Kim
Linear Carbon Chains Under High Pressure Conditions Journal Article
In: The Journal of Physical Chemistry C, vol. 119, no. 19, pp. 10669–10676, 2015.
@article{Andrade2015,
title = {Linear Carbon Chains Under High Pressure Conditions},
author = {Nadia Ferreira Andrade, Acrísio L Aguiar, Yoong Ahm Kim, Morinobu Endo, Paulo TC Freire, Gustavo Bruneto, Douglas Soares Galvao, Mildred S Dresselhaus, Antonio Gomes Souza Filho},
url = {http://pubs.acs.org/doi/abs/10.1021/acs.jpcc.5b00902},
doi = {10.1021/acs.jpcc.5b00902},
year = {2015},
date = {2015-04-23},
journal = {The Journal of Physical Chemistry C},
volume = {119},
number = {19},
pages = {10669–10676},
abstract = {A high-pressure resonance Raman spectroscopy study of linear carbon chains encapsulated inside multiwalled carbon nanotubes (MWCNTs) is reported. While the frequencies of the tangential modes of carbon nanotubes (G band) harden as the pressure increases, the vibrational frequencies of the chain modes (around 1850 cm–1) decrease, thus indicating a softening of the carbon–carbon bonds in this 1D solid. Pressure-induced irreversible structural changes in the linear carbon chains are unveiled by the red shift in the vibrational modes when pressure is released. These results have been interpreted as being due to a coalescence of carbon chains, and this hypothesis is supported by state-of-the-art atomistic reactive molecular dynamics simulations.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
A high-pressure resonance Raman spectroscopy study of linear carbon chains encapsulated inside multiwalled carbon nanotubes (MWCNTs) is reported. While the frequencies of the tangential modes of carbon nanotubes (G band) harden as the pressure increases, the vibrational frequencies of the chain modes (around 1850 cm–1) decrease, thus indicating a softening of the carbon–carbon bonds in this 1D solid. Pressure-induced irreversible structural changes in the linear carbon chains are unveiled by the red shift in the vibrational modes when pressure is released. These results have been interpreted as being due to a coalescence of carbon chains, and this hypothesis is supported by state-of-the-art atomistic reactive molecular dynamics simulations.
123.
PAS Autreto MJ Lagos, J Bettini
Surface effects on the mechanical elongation of AuCu nanowires: De-alloying and the formation of mixed suspended atomic chains Journal Article
In: Journal of Applied Physics, vol. 117, no. 9, pp. 094301, 2015.
@article{Lagos2015,
title = {Surface effects on the mechanical elongation of AuCu nanowires: De-alloying and the formation of mixed suspended atomic chains},
author = {MJ Lagos, PAS Autreto, J Bettini, F Sato, SO Dantas, DS Galvao, D Ugarte},
url = {http://scitation.aip.org/content/aip/journal/jap/117/9/10.1063/1.4913625},
doi = {10.1063/1.4913625},
year = {2015},
date = {2015-03-07},
journal = {Journal of Applied Physics},
volume = {117},
number = {9},
pages = {094301},
abstract = {We report here an atomistic study of the mechanical deformation of Au x Cu (1− x ) atomic-size wires (nanowires (NWs)) by means of high resolution transmission electron microscopy experiments. Molecular dynamics simulations were also carried out in order to obtain deeper insights on the dynamical properties of stretched NWs. The mechanical properties are significantly dependent on the chemical composition that evolves in time at the junction; some structures exhibit a remarkable de-alloying behavior. Also, our results represent the first experimental realization of mixed linear atomic chains (LACs) among transition and noble metals; in particular, surface energies induce chemical gradients on NW surfaces that can be exploited to control the relative LAC compositions (different number of gold and copper atoms). The implications of these results for nanocatalysis and spin transport of one-atom-thick metal wires are addressed.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
We report here an atomistic study of the mechanical deformation of Au x Cu (1− x ) atomic-size wires (nanowires (NWs)) by means of high resolution transmission electron microscopy experiments. Molecular dynamics simulations were also carried out in order to obtain deeper insights on the dynamical properties of stretched NWs. The mechanical properties are significantly dependent on the chemical composition that evolves in time at the junction; some structures exhibit a remarkable de-alloying behavior. Also, our results represent the first experimental realization of mixed linear atomic chains (LACs) among transition and noble metals; in particular, surface energies induce chemical gradients on NW surfaces that can be exploited to control the relative LAC compositions (different number of gold and copper atoms). The implications of these results for nanocatalysis and spin transport of one-atom-thick metal wires are addressed.
124.
Eric Perim, Douglas S. Galvao
Novel Nanoscroll Structures from Carbon Nitride Layers Online
2015, (ArXiv Draft MRS Proceedings, 1726, mrsf14-1726-j05-02 (2015)).
@online{Perim2015,
title = {Novel Nanoscroll Structures from Carbon Nitride Layers},
author = {Eric Perim, Douglas S. Galvao},
url = {http://arxiv.org/abs/1502.00260},
year = {2015},
date = {2015-02-02},
abstract = {Nanoscrolls consist of sheets rolled up into a papyrus-like form. Their open ends produce great radial flexibility, which can be exploited for a large variety of applications, from actuators to hydrogen storage. They have been successfully synthesized from different materials, including carbon and boron nitride. In this work we have investigated, through fully atomistic molecular dynamics simulations, the dynamics of scroll formation for a series of graphene-like carbon nitride (CN) two-dimensional systems: g-CN, triazine-based (g-C3N4), and heptazine-based (g-C3N4). Carbon nitride (CN) structures have been attracting great attention since their prediction as super hard materials. Recently, graphene-like carbon nitride (g-CN) structures have been synthesized with distinct stoichiometry and morphologies. By combining these unique CN characteristics with the structural properties inherent to nanoscrolls new nanostructures with very attractive mechanical and electronic properties could be formed. Our results show that stable nanoscrolls can be formed for all of CN structures we have investigated here. As the CN sheets have been already synthesized, these new scrolled structures are perfectly feasible and within our present-day technology.},
note = {ArXiv Draft MRS Proceedings, 1726, mrsf14-1726-j05-02 (2015)},
keywords = {},
pubstate = {published},
tppubtype = {online}
}
Nanoscrolls consist of sheets rolled up into a papyrus-like form. Their open ends produce great radial flexibility, which can be exploited for a large variety of applications, from actuators to hydrogen storage. They have been successfully synthesized from different materials, including carbon and boron nitride. In this work we have investigated, through fully atomistic molecular dynamics simulations, the dynamics of scroll formation for a series of graphene-like carbon nitride (CN) two-dimensional systems: g-CN, triazine-based (g-C3N4), and heptazine-based (g-C3N4). Carbon nitride (CN) structures have been attracting great attention since their prediction as super hard materials. Recently, graphene-like carbon nitride (g-CN) structures have been synthesized with distinct stoichiometry and morphologies. By combining these unique CN characteristics with the structural properties inherent to nanoscrolls new nanostructures with very attractive mechanical and electronic properties could be formed. Our results show that stable nanoscrolls can be formed for all of CN structures we have investigated here. As the CN sheets have been already synthesized, these new scrolled structures are perfectly feasible and within our present-day technology.
125.
L. D. Machado E. Perim, D. S. Galvao
A Brief Review on Syntheses, Structures and Applications of Nanoscrolls Online
2015, (ArXiv draft of Frontiers in Materials, 1 pp. 31, 2014).
@online{Perim2015b,
title = {A Brief Review on Syntheses, Structures and Applications of Nanoscrolls},
author = {E. Perim, L. D. Machado, D. S. Galvao},
url = {http://arxiv.org/abs/1501.05711 },
year = {2015},
date = {2015-01-21},
journal = {arXiv preprint 1501.05711v1},
abstract = {Nanoscrolls are papyrus-like nanostructures which present unique properties due to their open ended morphology. These properties can be exploited in a plethora of technological applications, leading to the design of novel and interesting devices. During the past decade, significant advances in the synthesis and characterization of these structures have been made, but many challenges still remain. In this mini review we provide an overview on their history, experimental synthesis methods, basic properties and application perspectives.},
note = {ArXiv draft of Frontiers in Materials, 1 pp. 31, 2014},
keywords = {},
pubstate = {published},
tppubtype = {online}
}
Nanoscrolls are papyrus-like nanostructures which present unique properties due to their open ended morphology. These properties can be exploited in a plethora of technological applications, leading to the design of novel and interesting devices. During the past decade, significant advances in the synthesis and characterization of these structures have been made, but many challenges still remain. In this mini review we provide an overview on their history, experimental synthesis methods, basic properties and application perspectives.
126.
Pedro A. S. Autreto, Douglas S. Galvao
Site dependent hydrogenation in Graphynes: A Fully Atomistic Molecular Dynamics Investigation Online
2015, (ArXiv draft of MRS Proceedings, 1726, mrsf14-1726-j02-02 (2015)).
@online{Autreto2015,
title = {Site dependent hydrogenation in Graphynes: A Fully Atomistic Molecular Dynamics Investigation},
author = {Pedro A. S. Autreto, Douglas S. Galvao},
url = {http://arxiv.org/abs/1501.04521},
year = {2015},
date = {2015-01-19},
journal = {arXiv preprint 1501.04521},
abstract = {Graphyne is a generic name for a carbon allotrope family of 2D structures, where acetylenic groups connect benzenoid rings, with the coexistence of sp and sp2 hybridized carbon atoms. In this work we have investigated, through fully atomistic reactive molecular dynamics simulations, the dynamics and structural changes of the hydrogenation of ALPHA, BETA, GAMMA graphyne forms. Our results showed that the existence of different sites for hydrogen bonding, related to single and triple bonds, makes the process of incorporating hydrogen atoms into graphyne membranes much more complex than the graphene ones. Our results also show that hydrogenation reactions are strongly site dependent and that the sp-hybridized carbon atoms are the preferential sites to chemical attacks. In our cases, the effectiveness of the hydrogenation (estimated from the number of hydrogen atoms covalently bonded to carbon atoms) follows the ALPHA, BETA, GAMMA graphyne structure ordering.},
note = {ArXiv draft of MRS Proceedings, 1726, mrsf14-1726-j02-02 (2015)},
keywords = {},
pubstate = {published},
tppubtype = {online}
}
Graphyne is a generic name for a carbon allotrope family of 2D structures, where acetylenic groups connect benzenoid rings, with the coexistence of sp and sp2 hybridized carbon atoms. In this work we have investigated, through fully atomistic reactive molecular dynamics simulations, the dynamics and structural changes of the hydrogenation of ALPHA, BETA, GAMMA graphyne forms. Our results showed that the existence of different sites for hydrogen bonding, related to single and triple bonds, makes the process of incorporating hydrogen atoms into graphyne membranes much more complex than the graphene ones. Our results also show that hydrogenation reactions are strongly site dependent and that the sp-hybridized carbon atoms are the preferential sites to chemical attacks. In our cases, the effectiveness of the hydrogenation (estimated from the number of hydrogen atoms covalently bonded to carbon atoms) follows the ALPHA, BETA, GAMMA graphyne structure ordering.
127.
Leonardo D. Machado Cristiano F. Woellner, Pedro A. S. Autreto
The Influence of Morphology on the Charge Transport in Two-Phase Disordered Organic Systems Online
2015, (ArXiv draft of MRS Proceedings, 1737, mrsf14-1737-u18-21 (2015)).
@online{Woellner2015,
title = {The Influence of Morphology on the Charge Transport in Two-Phase Disordered Organic Systems},
author = {Cristiano F. Woellner, Leonardo D. Machado, Pedro A. S. Autreto, Jose A. Freire, Douglas S. Galvao},
url = {http://arxiv.org/abs/1501.01343},
year = {2015},
date = {2015-01-01},
booktitle = {MRS Proceedings},
volume = {1737},
pages = {mrsf14-1737-u18-21},
abstract = {In this work we use a three-dimensional Pauli master equation to investigate the charge carrier mobility of a two-phase system, which can mimic donor-acceptor and amorphous- crystalline bulk heterojunctions. Our approach can be separated into two parts: the morphology generation and the charge transport modeling in the generated blend. The morphology part is based on a Monte Carlo simulation of binary mixtures (donor/acceptor). The second part is carried out by numerically solving the steady-state Pauli master equation. By taking the energetic disorder of each phase, their energy offset and domain morphology into consideration, we show that the carrier mobility can have a significant different behavior when compared to a one-phase system. When the energy offset is non-zero, we show that the mobility electric field dependence switches from negative to positive at a threshold field proportional to the energy offset. Additionally, the influence of morphology, through the domain size and the interfacial roughness parameters, on the transport was also investigated.},
note = {ArXiv draft of MRS Proceedings, 1737, mrsf14-1737-u18-21 (2015)},
keywords = {},
pubstate = {published},
tppubtype = {online}
}
In this work we use a three-dimensional Pauli master equation to investigate the charge carrier mobility of a two-phase system, which can mimic donor-acceptor and amorphous- crystalline bulk heterojunctions. Our approach can be separated into two parts: the morphology generation and the charge transport modeling in the generated blend. The morphology part is based on a Monte Carlo simulation of binary mixtures (donor/acceptor). The second part is carried out by numerically solving the steady-state Pauli master equation. By taking the energetic disorder of each phase, their energy offset and domain morphology into consideration, we show that the carrier mobility can have a significant different behavior when compared to a one-phase system. When the energy offset is non-zero, we show that the mobility electric field dependence switches from negative to positive at a threshold field proportional to the energy offset. Additionally, the influence of morphology, through the domain size and the interfacial roughness parameters, on the transport was also investigated.
128.
Leonardo D Machado Cristiano F Woellner, Pedro AS Autreto
The Influence of Morphology on the Charge Transport in Two-Phase Disordered Organic Systems Proceedings
vol. 1737, no. mrsf14-1737-u18-21, 2015, (MRS Proceedings, 1737, mrsf14-1737-u18-21).
@proceedings{Woellner2015b,
title = {The Influence of Morphology on the Charge Transport in Two-Phase Disordered Organic Systems},
author = {Cristiano F Woellner, Leonardo D Machado, Pedro AS Autreto, José A Freire, Douglas S Galvão},
url = {http://journals.cambridge.org/action/displayAbstract?fromPage=online&aid=9707375&fileId=S1946427415005023},
doi = {10.1557/opl.2015.502},
year = {2015},
date = {2015-01-01},
booktitle = {MRS Proceedings},
volume = {1737},
number = {mrsf14-1737-u18-21},
pages = {mrsf14-1737-u18-21},
abstract = {In this work we use a three-dimensional Pauli master equation to investigate the charge carrier mobility of a two-phase system, which can mimic donor-acceptor and amorphous-crystalline bulk heterojunctions. Our approach can be separated into two parts: the morphology generation and the charge transport modeling in the generated blend. The morphology part is based on a Monte Carlo simulation of binary mixtures (donor/acceptor). The second part is carried out by numerically solving the steady-state Pauli master equation. By taking the energetic disorder of each phase, their energy offset and domain morphology into consideration, we show that the carrier mobility can have a significant different behavior when compared to a one-phase system. When the energy offset is non-zero, we show that the mobility electric field dependence switches from negative to positive at a threshold field proportional to the energy offset. Additionally, the influence of morphology, through the domain size and the interfacial roughness parameters, on the transport was also investigated.
},
note = {MRS Proceedings, 1737, mrsf14-1737-u18-21},
keywords = {},
pubstate = {published},
tppubtype = {proceedings}
}
In this work we use a three-dimensional Pauli master equation to investigate the charge carrier mobility of a two-phase system, which can mimic donor-acceptor and amorphous-crystalline bulk heterojunctions. Our approach can be separated into two parts: the morphology generation and the charge transport modeling in the generated blend. The morphology part is based on a Monte Carlo simulation of binary mixtures (donor/acceptor). The second part is carried out by numerically solving the steady-state Pauli master equation. By taking the energetic disorder of each phase, their energy offset and domain morphology into consideration, we show that the carrier mobility can have a significant different behavior when compared to a one-phase system. When the energy offset is non-zero, we show that the mobility electric field dependence switches from negative to positive at a threshold field proportional to the energy offset. Additionally, the influence of morphology, through the domain size and the interfacial roughness parameters, on the transport was also investigated.
129.
Pedro A. S. Autreto, Douglas S. Galvao
Site Dependent Hydrogenation in Graphynes: A Fully Atomistic Molecular Dynamics Investigation Proceedings
vol. 1726, no. mrsf14-1726-j02-02, 2015, (MRS Proceedings, 1726, mrsf14-1726-j02-02 ).
@proceedings{Autreto2015b,
title = {Site Dependent Hydrogenation in Graphynes: A Fully Atomistic Molecular Dynamics Investigation},
author = {Pedro A. S. Autreto, Douglas S. Galvao},
url = {http://journals.cambridge.org/action/displayAbstract?fromPage=online&aid=9702693&fulltextType=RA&fileId=S1946427415004649},
doi = {10.1557/opl.2015.464},
year = {2015},
date = {2015-01-01},
journal = {Mater. Res. Soc. Symp. Proc. },
volume = {1726},
number = {mrsf14-1726-j02-02},
abstract = {Graphyne is a generic name for a carbon allotrope family of 2D structures, where acetylenic groups connect benzenoid rings, with the coexistence of sp and sp2 hybridized carbon atoms. In this work we have investigated, through fully atomistic reactive molecular dynamics simulations, the dynamics and structural changes of the hydrogenation of α, β, and γ graphyne forms. Our results showed that the existence of different sites for hydrogen bonding, related to single and triple bonds, makes the process of incorporating hydrogen atoms into graphyne membranes much more complex than the graphene ones. Our results also show that hydrogenation reactions are strongly site dependent and that the sp-hybridized carbon atoms are the preferential sites to chemical attacks. In our cases, the effectiveness of the hydrogenation (estimated from the number of hydrogen atoms covalently bonded to carbon atoms) follows the α, β, γ-graphyne structure ordering.},
note = {MRS Proceedings, 1726, mrsf14-1726-j02-02 },
keywords = {},
pubstate = {published},
tppubtype = {proceedings}
}
Graphyne is a generic name for a carbon allotrope family of 2D structures, where acetylenic groups connect benzenoid rings, with the coexistence of sp and sp2 hybridized carbon atoms. In this work we have investigated, through fully atomistic reactive molecular dynamics simulations, the dynamics and structural changes of the hydrogenation of α, β, and γ graphyne forms. Our results showed that the existence of different sites for hydrogen bonding, related to single and triple bonds, makes the process of incorporating hydrogen atoms into graphyne membranes much more complex than the graphene ones. Our results also show that hydrogenation reactions are strongly site dependent and that the sp-hybridized carbon atoms are the preferential sites to chemical attacks. In our cases, the effectiveness of the hydrogenation (estimated from the number of hydrogen atoms covalently bonded to carbon atoms) follows the α, β, γ-graphyne structure ordering.
130.
Eric Perim, Douglas S. Galvao
Novel Nanoscroll Structures from Carbon Nitride Layers Proceedings
vol. 1726, no. mrsf14-1726-j05-02, 2015, (MRS Proceedings, 1726, mrsf14-1726-j05-02 ).
@proceedings{Perim2015b,
title = {Novel Nanoscroll Structures from Carbon Nitride Layers},
author = {Eric Perim, Douglas S. Galvao},
url = {http://journals.cambridge.org/action/displayAbstract?fromPage=online&aid=9700860&fileId=S1946427415004650},
doi = {DOI: 10.1557/opl.2015.465},
year = {2015},
date = {2015-01-01},
volume = {1726},
number = {mrsf14-1726-j05-02},
abstract = {Nanoscrolls consist of sheets rolled up into a papyrus-like form. Their open ends produce great radial flexibility, which can be exploited for a large variety of applications, from actuators to hydrogen storage. They have been successfully synthesized from different materials, including carbon and boron nitride. In this work we have investigated, through fully atomistic molecular dynamics simulations, the dynamics of scroll formation for a series of graphene-like carbon nitride (CN) two-dimensional systems: g-CN, triazine-based (g-C3N4), and heptazine-based (g-C3N4). Carbon nitride (CN) structures have been attracting great attention since their prediction as super hard materials. Recently, graphene-like carbon nitride (g-CN) structures have been synthesized with distinct stoichiometry and morphologies. By combining these unique CN characteristics with the structural properties inherent to nanoscrolls new nanostructures with very attractive mechanical and electronic properties could be formed. Our results show that stable nanoscrolls can be formed for all of CN structures we have investigated here. As the CN sheets have been already synthesized, these new scrolled structures are perfectly feasible and within our present-day technology.},
note = {MRS Proceedings, 1726, mrsf14-1726-j05-02 },
keywords = {},
pubstate = {published},
tppubtype = {proceedings}
}
Nanoscrolls consist of sheets rolled up into a papyrus-like form. Their open ends produce great radial flexibility, which can be exploited for a large variety of applications, from actuators to hydrogen storage. They have been successfully synthesized from different materials, including carbon and boron nitride. In this work we have investigated, through fully atomistic molecular dynamics simulations, the dynamics of scroll formation for a series of graphene-like carbon nitride (CN) two-dimensional systems: g-CN, triazine-based (g-C3N4), and heptazine-based (g-C3N4). Carbon nitride (CN) structures have been attracting great attention since their prediction as super hard materials. Recently, graphene-like carbon nitride (g-CN) structures have been synthesized with distinct stoichiometry and morphologies. By combining these unique CN characteristics with the structural properties inherent to nanoscrolls new nanostructures with very attractive mechanical and electronic properties could be formed. Our results show that stable nanoscrolls can be formed for all of CN structures we have investigated here. As the CN sheets have been already synthesized, these new scrolled structures are perfectly feasible and within our present-day technology.
131.
Nadia F. Andradea Gustavo Brunettoa, Douglas S. Galvao
High Pressure Induced Binding Between Linear Carbon Chains and Nanotubes Proceedings
vol. 1752, no. 53-58, 2015, (MRS Proceedings, 1752, pp 53-58).
@proceedings{Brunettoa2015,
title = {High Pressure Induced Binding Between Linear Carbon Chains and Nanotubes},
author = {Gustavo Brunettoa, Nadia F. Andradea, Douglas S. Galvao, Antonio G. Souza Filho},
url = {http://journals.cambridge.org/action/displayAbstract?fromPage=online&aid=9553206&fileId=S1946427415000913},
doi = {10.1557/opl.2015.91},
year = {2015},
date = {2015-01-01},
volume = {1752},
number = {53-58},
abstract = {Recent studies of single-walled carbon nanotubes (CNTs) in aqueous media have showed that water can significantly affect the tube mechanical properties. CNTs under hydrostatic compression can preserve their elastic properties up to large pressure values, while exhibiting exceptional resistance to mechanical loadings. It was experimentally observed that CNTs with encapsulated linear carbon chains (LCCs), when subjected to high hydrostatic pressure values, present irreversible red shifts in some of their vibrational frequencies. In order to address the cause of this phenomenon, we have carried out fully atomistic reactive (ReaxFF) molecular dynamics (MD) simulations for model structures mimicking the experimental conditions. We have considered the cases of finite and infinite (cyclic boundary conditions) CNTs filled with LCCs (LCC@CNTs) of different lengths (from 9 up to 40 atoms). Our results show that increasing the hydrostatic pressure causes the CNT to be deformed in an inhomogeneous way due to the LCC presence. The LCC/CNT interface regions exhibit convex curvatures, which results in more reactive sites, thus favoring the formation of covalent chemical bonds between the chain and the nanotube. This process is irreversible with the newly formed bonds continuing to exist even after releasing the external pressure and causing an irreversibly red shift in the chain vibrational modes from 1850 to 1500 cm−1.},
note = {MRS Proceedings, 1752, pp 53-58},
keywords = {},
pubstate = {published},
tppubtype = {proceedings}
}
Recent studies of single-walled carbon nanotubes (CNTs) in aqueous media have showed that water can significantly affect the tube mechanical properties. CNTs under hydrostatic compression can preserve their elastic properties up to large pressure values, while exhibiting exceptional resistance to mechanical loadings. It was experimentally observed that CNTs with encapsulated linear carbon chains (LCCs), when subjected to high hydrostatic pressure values, present irreversible red shifts in some of their vibrational frequencies. In order to address the cause of this phenomenon, we have carried out fully atomistic reactive (ReaxFF) molecular dynamics (MD) simulations for model structures mimicking the experimental conditions. We have considered the cases of finite and infinite (cyclic boundary conditions) CNTs filled with LCCs (LCC@CNTs) of different lengths (from 9 up to 40 atoms). Our results show that increasing the hydrostatic pressure causes the CNT to be deformed in an inhomogeneous way due to the LCC presence. The LCC/CNT interface regions exhibit convex curvatures, which results in more reactive sites, thus favoring the formation of covalent chemical bonds between the chain and the nanotube. This process is irreversible with the newly formed bonds continuing to exist even after releasing the external pressure and causing an irreversibly red shift in the chain vibrational modes from 1850 to 1500 cm−1.
132.
Perim, Eric; Machado, Leonardo Dantas; Galvao, Douglas Soares
A Brief Review on Syntheses, Structures, and Applications of Nanoscrolls Journal Article
In: Frontiers in Materials, vol. 1, pp. 31, 2014, (Invited Review Paper).
@article{perim2014brief,
title = {A Brief Review on Syntheses, Structures, and Applications of Nanoscrolls},
author = {Perim, Eric and Machado, Leonardo Dantas and Galvao, Douglas Soares},
url = {http://journal.frontiersin.org/Journal/10.3389/fmats.2014.00031/abstract},
year = {2014},
date = {2014-12-01},
journal = {Frontiers in Materials},
volume = {1},
pages = {31},
publisher = {Frontiers},
abstract = {Nanoscrolls are papyrus-like nanostructures, which present unique properties due to their open ended morphology. These properties can be exploited in a plethora of technological applications, leading to the design of novel and interesting devices. During the past decade, significant advances in the synthesis and characterization of these structures have been made, but many challenges still remain. In this mini review, we provide an overview on their history, experimental synthesis methods, basic properties, and application perspectives.},
note = {Invited Review Paper},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Nanoscrolls are papyrus-like nanostructures, which present unique properties due to their open ended morphology. These properties can be exploited in a plethora of technological applications, leading to the design of novel and interesting devices. During the past decade, significant advances in the synthesis and characterization of these structures have been made, but many challenges still remain. In this mini review, we provide an overview on their history, experimental synthesis methods, basic properties, and application perspectives.
133.
Perim, E; Paupitz, R; Botari, T; Galvao, DS
One-dimensional silicon and germanium nanostructures with no carbon analogues Journal Article
In: Physical Chemistry Chemical Physics, vol. 16, no. 44, pp. 24570–24574, 2014.
@article{perim2014one,
title = {One-dimensional silicon and germanium nanostructures with no carbon analogues},
author = {Perim, E and Paupitz, R and Botari, T and Galvao, DS},
url = {http://pubs.rsc.org/en/content/articlehtml/2014/cp/c4cp03708a},
year = {2014},
date = {2014-01-01},
journal = {Physical Chemistry Chemical Physics},
volume = {16},
number = {44},
pages = {24570--24574},
publisher = {Royal Society of Chemistry},
abstract = {In this work we report new silicon and germanium tubular nanostructures with no corresponding stable carbon analogues. The electronic and mechanical properties of these new tubes were investigated through ab initio methods. Our results show that these structures have lower energy than their corresponding nanoribbon structures and are stable up to high temperatures (500 and 1000 K, for silicon and germanium tubes, respectively). Both tubes are semiconducting with small indirect band gaps, which can be significantly altered by both compressive and tensile strains. Large bandgap variations of almost 50% were observed for strain rates as small as 3%, suggesting their possible applications in sensor devices. They also present high Young's modulus values (0.25 and 0.15 TPa, respectively). TEM images were simulated to help in the identification of these new structures.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
In this work we report new silicon and germanium tubular nanostructures with no corresponding stable carbon analogues. The electronic and mechanical properties of these new tubes were investigated through ab initio methods. Our results show that these structures have lower energy than their corresponding nanoribbon structures and are stable up to high temperatures (500 and 1000 K, for silicon and germanium tubes, respectively). Both tubes are semiconducting with small indirect band gaps, which can be significantly altered by both compressive and tensile strains. Large bandgap variations of almost 50% were observed for strain rates as small as 3%, suggesting their possible applications in sensor devices. They also present high Young's modulus values (0.25 and 0.15 TPa, respectively). TEM images were simulated to help in the identification of these new structures.
134.
Botari, T; Perim, E; Autreto, PAS; van Duin, ACT; Paupitz, R; Galvao, DS
Mechanical properties and fracture dynamics of silicene membranes Journal Article
In: PHYSICAL CHEMISTRY CHEMICAL PHYSICS, vol. 16, no. 36, pp. 19417–19423, 2014.
@article{botari2014mechanical,
title = {Mechanical properties and fracture dynamics of silicene membranes},
author = {Botari, T and Perim, E and Autreto, PAS and van Duin, ACT and Paupitz, R and Galvao, DS},
url = {http://pubs.rsc.org/en/content/articlehtml/2014/cp/c4cp02902j},
year = {2014},
date = {2014-01-01},
journal = {PHYSICAL CHEMISTRY CHEMICAL PHYSICS},
volume = {16},
number = {36},
pages = {19417--19423},
publisher = {ROYAL SOC CHEMISTRY},
abstract = {As graphene has become one of the most important materials, there is renewed interest in other similar structures. One example is silicene, the silicon analogue of graphene. It shares some of the remarkable graphene properties, such as the Dirac cone, but presents some distinct ones, such as a pronounced structural buckling. We have investigated, through density functional based tight-binding (DFTB), as well as reactive molecular dynamics (using ReaxFF), the mechanical properties of suspended single-layer silicene. We calculated the elastic constants, analyzed the fracture patterns and edge reconstructions. We also addressed the stress distributions, unbuckling mechanisms and the fracture dependence on the temperature. We analysed the differences due to distinct edge morphologies, namely zigzag and armchair.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
As graphene has become one of the most important materials, there is renewed interest in other similar structures. One example is silicene, the silicon analogue of graphene. It shares some of the remarkable graphene properties, such as the Dirac cone, but presents some distinct ones, such as a pronounced structural buckling. We have investigated, through density functional based tight-binding (DFTB), as well as reactive molecular dynamics (using ReaxFF), the mechanical properties of suspended single-layer silicene. We calculated the elastic constants, analyzed the fracture patterns and edge reconstructions. We also addressed the stress distributions, unbuckling mechanisms and the fracture dependence on the temperature. We analysed the differences due to distinct edge morphologies, namely zigzag and armchair.
135.
Brunetto, Gustavo; Andrade, Nadia F.; Galvao, Douglas S; Antonio Filho, G Souza
High Pressure Induced Binding Between Linear Carbon Chains and Nanotubes Proceedings
2014.
@proceedings{brunetto2014high,
title = {High Pressure Induced Binding Between Linear Carbon Chains and Nanotubes},
author = {Brunetto, Gustavo and Andrade, Nadia F. and Galvao, Douglas S and Antonio Filho, G Souza},
url = {http://arxiv.org/abs/1412.7966},
year = {2014},
date = {2014-01-01},
journal = {arXiv preprint arXiv:1412.7966},
abstract = {Recent studies of single-walled carbon nanotubes (CNTs) in aqueous media have showed that water can significantly affect the tube mechanical properties. CNTs under hydrostatic compression can preserve their elastic properties up to large pressure values, while exhibiting exceptional resistance to mechanical loadings. It was experimentally observed that CNTs with encapsulated linear carbon chains (LCCs), when subjected to high hydrostatic pressure values, present irreversible red shifts in some of their vibrational frequencies. In order to address the cause of this phenomenon, we have carried out fully atomistic reactive (ReaxFF) molecular dynamics (MD) simulations for model structures mimicking the experimental conditions. We have considered the cases of finite and infinite (cyclic boundary conditions) CNTs filled with LCCs (LCC inside CNTs) of different lengths (from 9 up to 40 atoms). Our results show that increasing the hydrostatic pressure causes the CNT to be deformed in an inhomogeneous way due to the LCC presence. The LCC-CNT interface regions exhibit convex curvatures, which results in more reactive sites, thus favoring the formation of covalent chemical bonds between the chain and the nanotube. This process is irreversible with the newly formed bonds continuing to exist even after releasing the external pressure and causing an irreversibly red shift in the chain vibrational modes from 1850 to 1500 cm−1.},
keywords = {},
pubstate = {published},
tppubtype = {proceedings}
}
Recent studies of single-walled carbon nanotubes (CNTs) in aqueous media have showed that water can significantly affect the tube mechanical properties. CNTs under hydrostatic compression can preserve their elastic properties up to large pressure values, while exhibiting exceptional resistance to mechanical loadings. It was experimentally observed that CNTs with encapsulated linear carbon chains (LCCs), when subjected to high hydrostatic pressure values, present irreversible red shifts in some of their vibrational frequencies. In order to address the cause of this phenomenon, we have carried out fully atomistic reactive (ReaxFF) molecular dynamics (MD) simulations for model structures mimicking the experimental conditions. We have considered the cases of finite and infinite (cyclic boundary conditions) CNTs filled with LCCs (LCC inside CNTs) of different lengths (from 9 up to 40 atoms). Our results show that increasing the hydrostatic pressure causes the CNT to be deformed in an inhomogeneous way due to the LCC presence. The LCC-CNT interface regions exhibit convex curvatures, which results in more reactive sites, thus favoring the formation of covalent chemical bonds between the chain and the nanotube. This process is irreversible with the newly formed bonds continuing to exist even after releasing the external pressure and causing an irreversibly red shift in the chain vibrational modes from 1850 to 1500 cm−1.
136.
da Silva Autreto, Pedro Alves; Galvao, Douglas S.; Artacho, Emilio
Species fractionation in atomic chains from mechanically stretched alloys Journal Article
In: JOURNAL OF PHYSICS-CONDENSED MATTER, vol. 26, no. 43, 2014, ISSN: 0953-8984.
@article{daAutreto2014,
title = {Species fractionation in atomic chains from mechanically stretched alloys},
author = {da Silva Autreto, Pedro Alves and Galvao, Douglas S. and Artacho, Emilio},
issn = {0953-8984},
year = {2014},
date = {2014-01-01},
journal = {JOURNAL OF PHYSICS-CONDENSED MATTER},
volume = {26},
number = {43},
abstract = {Bettini et al (2006 Nat. Nanotechnol. 1 182-5) reported the first experimental realization of linear atomic chains (LACs) composed of different atoms (Au and Ag). The different contents of Au and Ag were observed in the chains from what was found in the bulk alloys, which raises the question of what the wire composition is, if it is in equilibrium with a bulk alloy. In this work we address the thermodynamic driving force for species fractionation in LACs under tension, and we present the density-functional theory results for Ag-Au chain alloys. A pronounced stabilization of the wires with an alternating Ag-Au sequence is observed, which could be behind the experimentally observed Au enrichment in LACs from alloys with high Ag content.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Bettini et al (2006 Nat. Nanotechnol. 1 182-5) reported the first experimental realization of linear atomic chains (LACs) composed of different atoms (Au and Ag). The different contents of Au and Ag were observed in the chains from what was found in the bulk alloys, which raises the question of what the wire composition is, if it is in equilibrium with a bulk alloy. In this work we address the thermodynamic driving force for species fractionation in LACs under tension, and we present the density-functional theory results for Ag-Au chain alloys. A pronounced stabilization of the wires with an alternating Ag-Au sequence is observed, which could be behind the experimentally observed Au enrichment in LACs from alloys with high Ag content.
137.
Gao, Guanhui; Mathkar, Akshay; Martins, Eric Perim; Galvao, Douglas S; Gao, Duyang; da Silva Autreto, Pedro Alves; Sun, Chengjun; Cai, Lintao; Ajayan, Pulickel M
Designing nanoscaled hybrids from atomic layered boron nitride with silver nanoparticle deposition Journal Article
In: Journal of Materials Chemistry A, vol. 2, no. 9, pp. 3148–3154, 2014.
@article{gao2014designing,
title = {Designing nanoscaled hybrids from atomic layered boron nitride with silver nanoparticle deposition},
author = {Gao, Guanhui and Mathkar, Akshay and Martins, Eric Perim and Galvao, Douglas S and Gao, Duyang and da Silva Autreto, Pedro Alves and Sun, Chengjun and Cai, Lintao and Ajayan, Pulickel M},
url = {http://pubs.rsc.org/en/Content/ArticleLanding/2014/TA/c3ta12892j#!divAbstract},
year = {2014},
date = {2014-01-01},
journal = {Journal of Materials Chemistry A},
volume = {2},
number = {9},
pages = {3148--3154},
publisher = {Royal Society of Chemistry},
abstract = {We have developed a microwave assisted one-pot approach to fabricate a novel hybrid nano-composite composed of two-dimensional chemically exfoliated layered hexagonal boron nitride (h-BN) and embedded silver nanoparticles (SNP). Atomic layered h-BN exfoliated using chemical liquid showed strong in-plane bonding and weak van der Waals interplanar interactions, which is utilized for chemically interfacing SNP, indicating their ability to act as excellent nano-scaffolds. The SNP/h-BN optical response, in particular band gap, is strongly dependent on the concentration of the metallic particles. In order to gain further insight into this behavior we have also carried out ab initio density functional theory (DFT) calculations on modeled structures, demonstrating that the bandgap value of SNP/h-BN hybrids could be significantly altered by a small percentage of OH− groups located at dangling B and N atoms. Our results showed that these novel SNP/h-BN nanohybrid structures exhibited excellent thermal stability and they are expected to be applied as devices for thermal oxidation-resistant surface enhanced Raman spectroscopy (SERS). The SNP/h-BN membrane showed remarkable antibacterial activity, suggesting their potential use in water disinfection and food packaging.
},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
We have developed a microwave assisted one-pot approach to fabricate a novel hybrid nano-composite composed of two-dimensional chemically exfoliated layered hexagonal boron nitride (h-BN) and embedded silver nanoparticles (SNP). Atomic layered h-BN exfoliated using chemical liquid showed strong in-plane bonding and weak van der Waals interplanar interactions, which is utilized for chemically interfacing SNP, indicating their ability to act as excellent nano-scaffolds. The SNP/h-BN optical response, in particular band gap, is strongly dependent on the concentration of the metallic particles. In order to gain further insight into this behavior we have also carried out ab initio density functional theory (DFT) calculations on modeled structures, demonstrating that the bandgap value of SNP/h-BN hybrids could be significantly altered by a small percentage of OH− groups located at dangling B and N atoms. Our results showed that these novel SNP/h-BN nanohybrid structures exhibited excellent thermal stability and they are expected to be applied as devices for thermal oxidation-resistant surface enhanced Raman spectroscopy (SERS). The SNP/h-BN membrane showed remarkable antibacterial activity, suggesting their potential use in water disinfection and food packaging.
138.
Perim, E; Fonseca, AF; Pugno, NM; Galvao, DS
Violation of the universal behavior of membranes inside cylindrical tubes at nanoscale Journal Article
In: EPL (Europhysics Letters), vol. 105, no. 5, pp. 56002, 2014.
@article{perim2014violation,
title = {Violation of the universal behavior of membranes inside cylindrical tubes at nanoscale},
author = {Perim, E and Fonseca, AF and Pugno, NM and Galvao, DS},
url = {http://iopscience.iop.org/0295-5075/105/5/56002},
year = {2014},
date = {2014-01-01},
journal = {EPL (Europhysics Letters)},
volume = {105},
number = {5},
pages = {56002},
publisher = {IOP Publishing},
abstract = {Recently, it was proposed based on classical elasticity theory and experiments at macroscale, that the conformations of sheets inside cylindrical tubes present a universal behavior. A natural question is whether this behavior still holds at nanoscale. Based on molecular-dynamics simulations and analytical modeling for graphene and boron nitride membranes confined inside carbon nanotubes, we show that the class of universality observed at macroscale is violated at nanoscale. The precise origin of these discrepancies is addressed and proven to be related to both surface and atomistic effects.
},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Recently, it was proposed based on classical elasticity theory and experiments at macroscale, that the conformations of sheets inside cylindrical tubes present a universal behavior. A natural question is whether this behavior still holds at nanoscale. Based on molecular-dynamics simulations and analytical modeling for graphene and boron nitride membranes confined inside carbon nanotubes, we show that the class of universality observed at macroscale is violated at nanoscale. The precise origin of these discrepancies is addressed and proven to be related to both surface and atomistic effects.
139.
Perim, Eric; Paupitz, Ricardo; Botari, Tiago; Galvao, Douglas S
Novel Semiconducting Silicon and Germanium Nanotubes Journal Article
In: arXiv preprint arXiv:1403.2061, 2014.
@article{perim2014novel,
title = {Novel Semiconducting Silicon and Germanium Nanotubes},
author = {Perim, Eric and Paupitz, Ricardo and Botari, Tiago and Galvao, Douglas S},
url = {http://arxiv.org/abs/1403.2061},
year = {2014},
date = {2014-01-01},
journal = {arXiv preprint arXiv:1403.2061},
abstract = {In this work we report new silicon and germanium nanotube structures, with no corresponding
stable carbon analogues and which cannot be described by integer chiral indices. The electronic
and mechanical properties of these new tubes were investigated through ab initio methods. Our
results show that the structures are stable up to high temperatures (500 and 1000 K, for silicon and
germanium tubes, respectively). Both tubes are semiconducting with small indirect band gaps,
which can be significantly altered by both compressive and tensile strains. They also present high
Young modulus values (0.25 and 0.15 TPa, respectively).},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
In this work we report new silicon and germanium nanotube structures, with no corresponding
stable carbon analogues and which cannot be described by integer chiral indices. The electronic
and mechanical properties of these new tubes were investigated through ab initio methods. Our
results show that the structures are stable up to high temperatures (500 and 1000 K, for silicon and
germanium tubes, respectively). Both tubes are semiconducting with small indirect band gaps,
which can be significantly altered by both compressive and tensile strains. They also present high
Young modulus values (0.25 and 0.15 TPa, respectively).
stable carbon analogues and which cannot be described by integer chiral indices. The electronic
and mechanical properties of these new tubes were investigated through ab initio methods. Our
results show that the structures are stable up to high temperatures (500 and 1000 K, for silicon and
germanium tubes, respectively). Both tubes are semiconducting with small indirect band gaps,
which can be significantly altered by both compressive and tensile strains. They also present high
Young modulus values (0.25 and 0.15 TPa, respectively).
140.
Brunetto, G; Galvao, DS
Graphene-like Membranes: From Impermeable to Selective Sieves Proceedings
Cambridge University Press, vol. 1658, 2014.
@proceedings{brunetto2014graphene,
title = {Graphene-like Membranes: From Impermeable to Selective Sieves},
author = {Brunetto, G and Galvao, DS},
url = {http://journals.cambridge.org/action/displayAbstract?fromPage=online&aid=9248039&fileId=S1946427414004011},
year = {2014},
date = {2014-01-01},
journal = {MRS Proceedings},
volume = {1658},
pages = {mrsf13--1658},
publisher = {Cambridge University Press},
abstract = {Recently, it was proposed that graphene membranes could act as impermeable atomic
structures to standard gases. For some other applications, a higher level of porosity is needed,
and the so-called Porous Graphene (PG) and Biphenylene Carbon (BPC) membranes are good
candidates to effectively work as selective sieves. In this work we have used classical molecular
dynamics simulations to study the dynamics of membrane permeation of He and Ar atoms and
possible selectivity effects. For the graphene membranes we did not observe any leakage
through the membrane and/or membrane/substrate interface until a critical pressure limit, then a
sudden membrane detachment occurs. PG and BPC membranes are not impermeable as
graphene ones, but there are significant energy barriers to diffusion depending on the atom type.
Our results show that this kind of porous membranes can be effectively used as selective sieves
for pure and mixtures of gases.},
keywords = {},
pubstate = {published},
tppubtype = {proceedings}
}
Recently, it was proposed that graphene membranes could act as impermeable atomic
structures to standard gases. For some other applications, a higher level of porosity is needed,
and the so-called Porous Graphene (PG) and Biphenylene Carbon (BPC) membranes are good
candidates to effectively work as selective sieves. In this work we have used classical molecular
dynamics simulations to study the dynamics of membrane permeation of He and Ar atoms and
possible selectivity effects. For the graphene membranes we did not observe any leakage
through the membrane and/or membrane/substrate interface until a critical pressure limit, then a
sudden membrane detachment occurs. PG and BPC membranes are not impermeable as
graphene ones, but there are significant energy barriers to diffusion depending on the atom type.
Our results show that this kind of porous membranes can be effectively used as selective sieves
for pure and mixtures of gases.
structures to standard gases. For some other applications, a higher level of porosity is needed,
and the so-called Porous Graphene (PG) and Biphenylene Carbon (BPC) membranes are good
candidates to effectively work as selective sieves. In this work we have used classical molecular
dynamics simulations to study the dynamics of membrane permeation of He and Ar atoms and
possible selectivity effects. For the graphene membranes we did not observe any leakage
through the membrane and/or membrane/substrate interface until a critical pressure limit, then a
sudden membrane detachment occurs. PG and BPC membranes are not impermeable as
graphene ones, but there are significant energy barriers to diffusion depending on the atom type.
Our results show that this kind of porous membranes can be effectively used as selective sieves
for pure and mixtures of gases.
1999
86.
Vendrame, Rosana; Braga, RS; Takahata, Y; Galvao, DS
Structure-activity relationship studies of carcinogenic activity of polycyclic aromatic hydrocarbons using calculated molecular descriptors with principal component analysis and neural network methods Journal Article
In: Journal of chemical information and computer sciences, vol. 39, no. 6, pp. 1094–1104, 1999.
BibTeX | Tags:
@article{vendrame1999structure,
title = {Structure-activity relationship studies of carcinogenic activity of polycyclic aromatic hydrocarbons using calculated molecular descriptors with principal component analysis and neural network methods},
author = {Vendrame, Rosana and Braga, RS and Takahata, Y and Galvao, DS},
year = {1999},
date = {1999-01-01},
journal = {Journal of chemical information and computer sciences},
volume = {39},
number = {6},
pages = {1094--1104},
publisher = {American Chemical Society},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
85.
Braga, RS; Barone, PMVB; Galvao, DS
Identifying carcinogenic activity of methylated polycyclic aromatic hydrocarbons (PAHs) Journal Article
In: Journal of Molecular Structure: THEOCHEM, vol. 464, no. 1, pp. 257–266, 1999.
BibTeX | Tags:
@article{braga1999identifying,
title = {Identifying carcinogenic activity of methylated polycyclic aromatic hydrocarbons (PAHs)},
author = {Braga, RS and Barone, PMVB and Galvao, DS},
year = {1999},
date = {1999-01-01},
journal = {Journal of Molecular Structure: THEOCHEM},
volume = {464},
number = {1},
pages = {257--266},
publisher = {Elsevier},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
84.
Bolivar-Marinez, LE; Galvao, DS; Caldas, MJ
Geometric and spectroscopic study of some molecules related to eumelanins. 1. Monomers Journal Article
In: The Journal of Physical Chemistry B, vol. 103, no. 15, pp. 2993–3000, 1999.
BibTeX | Tags:
@article{bolivar1999geometric,
title = {Geometric and spectroscopic study of some molecules related to eumelanins. 1. Monomers},
author = {Bolivar-Marinez, LE and Galvao, DS and Caldas, MJ},
year = {1999},
date = {1999-01-01},
journal = {The Journal of Physical Chemistry B},
volume = {103},
number = {15},
pages = {2993--3000},
publisher = {ACS Publications},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
83.
Monomers, I; Bolivar-Marinez, LE; Galvao, DS; Caldas, MJ
Geometric and Spectroscopic Study of Some Molecules Related to Eumelanins Journal Article
In: JOURNAL OF PHYSICAL CHEMISTRY B, vol. 103, pp. 2993–3000, 1999.
BibTeX | Tags:
@article{monomers1999geometric,
title = {Geometric and Spectroscopic Study of Some Molecules Related to Eumelanins},
author = {Monomers, I and Bolivar-Marinez, LE and Galvao, DS and Caldas, MJ},
year = {1999},
date = {1999-01-01},
journal = {JOURNAL OF PHYSICAL CHEMISTRY B},
volume = {103},
pages = {2993--3000},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
82.
Cyrillo, M; Galv ao, DS
Structure--activity relationship study of some inhibitors of HIV-1 integrase Journal Article
In: Journal of Molecular Structure: THEOCHEM, vol. 464, no. 1, pp. 267–272, 1999.
BibTeX | Tags:
@article{cyrillo1999structure,
title = {Structure--activity relationship study of some inhibitors of HIV-1 integrase},
author = {Cyrillo, M and Galv~ao, DS},
year = {1999},
date = {1999-01-01},
journal = {Journal of Molecular Structure: THEOCHEM},
volume = {464},
number = {1},
pages = {267--272},
publisher = {Elsevier},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
81.
Barone, PMVB; Dantas, SO; Galv ao, DS
A semi--empirical study on the electronic structure of ellipticines Journal Article
In: Journal of Molecular Structure: THEOCHEM, vol. 465, no. 2, pp. 219–229, 1999.
BibTeX | Tags:
@article{barone1999semi,
title = {A semi--empirical study on the electronic structure of ellipticines},
author = {Barone, PMVB and Dantas, SO and Galv~ao, DS},
year = {1999},
date = {1999-01-01},
journal = {Journal of Molecular Structure: THEOCHEM},
volume = {465},
number = {2},
pages = {219--229},
publisher = {Elsevier},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
80.
Cyrillo, M; Galv ao, DS
Chem2Pac: A Computational Chemistry Integrator for Windows. Journal Article
In: EPA NEWSLETTER-EUROPEAN PHOTOCHEMISTRY ASSOCIATION, pp. 31–34, 1999.
BibTeX | Tags:
@article{cyrillo1999chem2pac,
title = {Chem2Pac: A Computational Chemistry Integrator for Windows.},
author = {Cyrillo, M and Galv~ao, DS},
year = {1999},
date = {1999-01-01},
journal = {EPA NEWSLETTER-EUROPEAN PHOTOCHEMISTRY ASSOCIATION},
pages = {31--34},
publisher = {EUROPEAN PHOTOCHEMISTRY ASSOCIATION},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
79.
Avanci, LH; Braga, RS; Cardoso, LP; Galvao, DS; Sherwood, JN
Hysteresislike Behavior in Meta-Nitroaniline Crystals Journal Article
In: Physical Review Letters, vol. 83, no. 24, pp. 5146, 1999.
BibTeX | Tags:
@article{avanci1999hysteresislike,
title = {Hysteresislike Behavior in Meta-Nitroaniline Crystals},
author = {Avanci, LH and Braga, RS and Cardoso, LP and Galvao, DS and Sherwood, JN},
year = {1999},
date = {1999-01-01},
journal = {Physical Review Letters},
volume = {83},
number = {24},
pages = {5146},
publisher = {American Physical Society},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
78.
Barone, PMVB; Dantas, SO; Galv ao, DS
A dual-mode photoswitching investigation Journal Article
In: Synthetic metals, vol. 102, no. 1, pp. 1454–1455, 1999.
BibTeX | Tags:
@article{barone1999dual,
title = {A dual-mode photoswitching investigation},
author = {Barone, PMVB and Dantas, SO and Galv~ao, DS},
year = {1999},
date = {1999-01-01},
journal = {Synthetic metals},
volume = {102},
number = {1},
pages = {1454--1455},
publisher = {Elsevier},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
77.
Barone, PMVB; Camilo Jr, A; Galv ao, DS
Theoretical characterization of oligocubanes Journal Article
In: Synthetic metals, vol. 102, no. 1, pp. 1410, 1999.
BibTeX | Tags:
@article{barone1999theoretical,
title = {Theoretical characterization of oligocubanes},
author = {Barone, PMVB and Camilo Jr, A and Galv~ao, DS},
year = {1999},
date = {1999-01-01},
journal = {Synthetic metals},
volume = {102},
number = {1},
pages = {1410},
publisher = {Elsevier},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
76.
Cyrillo, M; Galvao, DS
HyperSpin: Conformational Search Add-on to HyperChem^ T^ M. Journal Article
In: EPA NEWSLETTER-EUROPEAN PHOTOCHEMISTRY ASSOCIATION, pp. 34–38, 1999.
BibTeX | Tags:
@article{cyrillo1999hyperspin,
title = {HyperSpin: Conformational Search Add-on to HyperChem^ T^ M.},
author = {Cyrillo, M and Galvao, DS},
year = {1999},
date = {1999-01-01},
journal = {EPA NEWSLETTER-EUROPEAN PHOTOCHEMISTRY ASSOCIATION},
pages = {34--38},
publisher = {EUROPEAN PHOTOCHEMISTRY ASSOCIATION},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
75.
Santo, LL do E; Galv ao, DS
Structure--activity study of indolequinones bioreductive alkylating agents Journal Article
In: Journal of Molecular Structure: THEOCHEM, vol. 464, no. 1, pp. 273–279, 1999.
BibTeX | Tags:
@article{santo1999structure,
title = {Structure--activity study of indolequinones bioreductive alkylating agents},
author = {Santo, LL do E and Galv~ao, DS},
year = {1999},
date = {1999-01-01},
journal = {Journal of Molecular Structure: THEOCHEM},
volume = {464},
number = {1},
pages = {273--279},
publisher = {Elsevier},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
74.
PMVB, Barone; Galvao, DS
IDENTIFYING CARCINOGENIC ACTIVITY OF METHYLATED POLYCYCLIC AROMATIC HYDROCARBONS (PAHS) Journal Article
In: Computational and Theoretical Chemistry, vol. 464, 1999.
BibTeX | Tags:
@article{pmvb1999identifying,
title = {IDENTIFYING CARCINOGENIC ACTIVITY OF METHYLATED POLYCYCLIC AROMATIC HYDROCARBONS (PAHS)},
author = {PMVB, Barone and Galvao, DS},
year = {1999},
date = {1999-01-01},
journal = {Computational and Theoretical Chemistry},
volume = {464},
publisher = {Elsevier Science Publishing Company, Inc.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
1997
73.
Durrant, Steven F; Castro, Sandra GC; Bol'ivar-Marinez, Luz Elena; Galv ao, Douglas S; Bica de Moraes, M'ario A
Structural and optical properties of amorphous hydrogenated fluorinated carbon films produced by PECVD Journal Article
In: Thin Solid Films, vol. 304, no. 1, pp. 149–156, 1997.
BibTeX | Tags:
@article{durrant1997structural,
title = {Structural and optical properties of amorphous hydrogenated fluorinated carbon films produced by PECVD},
author = {Durrant, Steven F and Castro, Sandra GC and Bol'ivar-Marinez, Luz Elena and Galv~ao, Douglas S and Bica de Moraes, M'ario A},
year = {1997},
date = {1997-01-01},
journal = {Thin Solid Films},
volume = {304},
number = {1},
pages = {149--156},
publisher = {Elsevier},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
72.
Baughman, RH; Galvao, DS; Cui, C; Dantas, SO
Hinged and chiral polydiacetylene carbon crystals Journal Article
In: Chemical physics letters, vol. 269, no. 3, pp. 356–364, 1997.
BibTeX | Tags:
@article{baughman1997hinged,
title = {Hinged and chiral polydiacetylene carbon crystals},
author = {Baughman, RH and Galvao, DS and Cui, C and Dantas, SO},
year = {1997},
date = {1997-01-01},
journal = {Chemical physics letters},
volume = {269},
number = {3},
pages = {356--364},
publisher = {Elsevier},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
71.
Laks, B; Galv ao, DS
Extended states in interacting disordered polyacetylenelike chains Journal Article
In: Physical Review B, vol. 56, no. 3, pp. 967, 1997.
BibTeX | Tags:
@article{laks1997extended,
title = {Extended states in interacting disordered polyacetylenelike chains},
author = {Laks, B and Galv~ao, DS},
year = {1997},
date = {1997-01-01},
journal = {Physical Review B},
volume = {56},
number = {3},
pages = {967},
publisher = {APS},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
70.
Durrant, Steven F; de Oliveira, Ricardo T; Castro, Sandra GC; Galvao, Douglas S; Bica de Moraes, Mario A; others,
Structural and optical properties of plasma-deposited amorphous hydrogenated oxygenated carbon films Journal Article
In: Journal of Vacuum Science & Technology A: Vacuum, Surfaces, and Films, vol. 15, no. 3, pp. 1334–1339, 1997.
BibTeX | Tags:
@article{durrant1997structuralb,
title = {Structural and optical properties of plasma-deposited amorphous hydrogenated oxygenated carbon films},
author = {Durrant, Steven F and de Oliveira, Ricardo T and Castro, Sandra GC and Galvao, Douglas S and Bica de Moraes, Mario A and others},
year = {1997},
date = {1997-01-01},
journal = {Journal of Vacuum Science & Technology A: Vacuum, Surfaces, and Films},
volume = {15},
number = {3},
pages = {1334--1339},
publisher = {AVS},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
69.
Dantas, SO; Dos Santos, MC; Galvao, DS
Theoretical investigation of an all-organic molecular transistor Journal Article
In: Synthetic metals, vol. 85, no. 1, pp. 1143–1144, 1997.
BibTeX | Tags:
@article{dantas1997theoretical,
title = {Theoretical investigation of an all-organic molecular transistor},
author = {Dantas, SO and Dos Santos, MC and Galvao, DS},
year = {1997},
date = {1997-01-01},
journal = {Synthetic metals},
volume = {85},
number = {1},
pages = {1143--1144},
publisher = {Elsevier},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
68.
Bolivar-Marinez, LE; Dos Santos, MC; Galvao, DS
On the fluorescence of substituted oligothiophenes Journal Article
In: Synthetic metals, vol. 85, no. 1, pp. 1117–1118, 1997.
BibTeX | Tags:
@article{bolivar1997fluorescence,
title = {On the fluorescence of substituted oligothiophenes},
author = {Bolivar-Marinez, LE and Dos Santos, MC and Galvao, DS},
year = {1997},
date = {1997-01-01},
journal = {Synthetic metals},
volume = {85},
number = {1},
pages = {1117--1118},
publisher = {Elsevier},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
67.
Laks, B; Galv ao, DS
Extended states in interacting one-dimensional disordered polymeric chains Journal Article
In: Synthetic metals, vol. 85, no. 1, pp. 1125–1126, 1997.
BibTeX | Tags:
@article{laks1997extendedb,
title = {Extended states in interacting one-dimensional disordered polymeric chains},
author = {Laks, B and Galv~ao, DS},
year = {1997},
date = {1997-01-01},
journal = {Synthetic metals},
volume = {85},
number = {1},
pages = {1125--1126},
publisher = {Elsevier},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
1996
66.
A Camilo Jr PMVB Barone, DS Galvao
Theoretical approach to identify carcinogenic activity of polycyclic aromatic hydrocarbons Journal Article
In: Physical Review Letters, vol. 77, no. 6, pp. 1186, 1996.
Abstract | Links | BibTeX | Tags: top20
@article{barone1996theoretical,
title = {Theoretical approach to identify carcinogenic activity of polycyclic aromatic hydrocarbons},
author = {PMVB Barone, A Camilo Jr, DS Galvao},
url = {http://journals.aps.org/prl/abstract/10.1103/PhysRevLett.77.1186},
doi = {10.1103/PhysRevLett.77.1186},
year = {1996},
date = {1996-01-01},
journal = {Physical Review Letters},
volume = {77},
number = {6},
pages = {1186},
publisher = {American Physical Society},
abstract = {Polycyclic aromatic hydrocarbons (PAHs) are a class of planar molecules that can induce chemical carcinogenesis. Their carcinogenic powers vary in a large range, from the very strong carcinogens to the inactive ones. Many models have been proposed to explain the PAHs' carcinogenic activity, but all of them present some failures. Here we introduce a new methodology to identify PAHs' carcinogenic activity based on the concept of electronic local density of states (LDOS). We show that the analysis of the molecular energy levels in association with the LDOS calculated over the ring which contains the highest bond order of the molecule allows simple rules to identify whether a specific PAH molecule will present (or not) carcinogenic activity.},
keywords = {top20},
pubstate = {published},
tppubtype = {article}
}
Polycyclic aromatic hydrocarbons (PAHs) are a class of planar molecules that can induce chemical carcinogenesis. Their carcinogenic powers vary in a large range, from the very strong carcinogens to the inactive ones. Many models have been proposed to explain the PAHs' carcinogenic activity, but all of them present some failures. Here we introduce a new methodology to identify PAHs' carcinogenic activity based on the concept of electronic local density of states (LDOS). We show that the analysis of the molecular energy levels in association with the LDOS calculated over the ring which contains the highest bond order of the molecule allows simple rules to identify whether a specific PAH molecule will present (or not) carcinogenic activity.
65.
Bolivar-Marinez, LE; Dos Santos, MC; Galv ao, DS
Electronic structure of push-pull molecules based on thiophene oligomers Journal Article
In: The Journal of Physical Chemistry, vol. 100, no. 26, pp. 11029–11032, 1996.
BibTeX | Tags:
@article{bolivar1996electronic,
title = {Electronic structure of push-pull molecules based on thiophene oligomers},
author = {Bolivar-Marinez, LE and Dos Santos, MC and Galv~ao, DS},
year = {1996},
date = {1996-01-01},
journal = {The Journal of Physical Chemistry},
volume = {100},
number = {26},
pages = {11029--11032},
publisher = {American Chemical Society},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
64.
Dantas, SO; dos Santos, MC; Galvao, DS
Theoretical characterization of an all-organic molecular transistor Journal Article
In: Chemical physics letters, vol. 256, no. 1, pp. 207–212, 1996.
BibTeX | Tags:
@article{dantas1996theoretical,
title = {Theoretical characterization of an all-organic molecular transistor},
author = {Dantas, SO and dos Santos, MC and Galvao, DS},
year = {1996},
date = {1996-01-01},
journal = {Chemical physics letters},
volume = {256},
number = {1},
pages = {207--212},
publisher = {Elsevier},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
1995
63.
dos Santos, Maria C; Galvao, Douglas S; Teschke, O; Soares, DM
Spatially variable reaction in the formation of anodically grown porous silicon structure Proceedings Article
In: SPIE's 1995 International Symposium on Optical Science, Engineering, and Instrumentation, pp. 228–235, International Society for Optics and Photonics 1995.
BibTeX | Tags:
@inproceedings{dos1995spatially,
title = {Spatially variable reaction in the formation of anodically grown porous silicon structure},
author = {dos Santos, Maria C and Galvao, Douglas S and Teschke, O and Soares, DM},
year = {1995},
date = {1995-01-01},
booktitle = {SPIE's 1995 International Symposium on Optical Science, Engineering, and Instrumentation},
pages = {228--235},
organization = {International Society for Optics and Photonics},
keywords = {},
pubstate = {published},
tppubtype = {inproceedings}
}
62.
dos Santos, Maria C; Bolivar-Marinez, LE; Galvao, Douglas S
Theoretical study of push-pull molecules based on thiophene oligomers Proceedings Article
In: SPIE's 1995 International Symposium on Optical Science, Engineering, and Instrumentation, pp. 135–142, International Society for Optics and Photonics 1995.
BibTeX | Tags:
@inproceedings{dos1995theoreticalb,
title = {Theoretical study of push-pull molecules based on thiophene oligomers},
author = {dos Santos, Maria C and Bolivar-Marinez, LE and Galvao, Douglas S},
year = {1995},
date = {1995-01-01},
booktitle = {SPIE's 1995 International Symposium on Optical Science, Engineering, and Instrumentation},
pages = {135--142},
organization = {International Society for Optics and Photonics},
keywords = {},
pubstate = {published},
tppubtype = {inproceedings}
}
61.
Mota, Rog'erio Pinto; Galv ao, Douglas; Durrant, Steven F; De Moraes, M'ario A Bica; de Oliveira Dantas, Socrates; Cant ao, Mauricio
HMDSO plasma polymerization and thin film optical properties Journal Article
In: Thin Solid Films, vol. 270, no. 1, pp. 109–113, 1995.
BibTeX | Tags:
@article{mota1995hmdso,
title = {HMDSO plasma polymerization and thin film optical properties},
author = {Mota, Rog'erio Pinto and Galv~ao, Douglas and Durrant, Steven F and De Moraes, M'ario A Bica and de Oliveira Dantas, Socrates and Cant~ao, Mauricio},
year = {1995},
date = {1995-01-01},
journal = {Thin Solid Films},
volume = {270},
number = {1},
pages = {109--113},
publisher = {Elsevier},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
60.
Teschke, O; Dos Santos, MC; Kleinke, MU; Soares, DM; Galvao, DS
Spatially variable reaction in the formation of anodically grown porous silicon structures Journal Article
In: Journal of applied physics, vol. 78, no. 1, pp. 590–592, 1995.
BibTeX | Tags:
@article{teschke1995spatially,
title = {Spatially variable reaction in the formation of anodically grown porous silicon structures},
author = {Teschke, O and Dos Santos, MC and Kleinke, MU and Soares, DM and Galvao, DS},
year = {1995},
date = {1995-01-01},
journal = {Journal of applied physics},
volume = {78},
number = {1},
pages = {590--592},
publisher = {AIP Publishing},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
59.
Baughman, RH; Galvao, DS
Negative volumetric thermal expansion for proposed hinged phases Journal Article
In: Chemical Physics Letters, vol. 240, no. 1, pp. 180–184, 1995.
BibTeX | Tags:
@article{baughman1995negative,
title = {Negative volumetric thermal expansion for proposed hinged phases},
author = {RH Baughman and DS Galvao},
year = {1995},
date = {1995-01-01},
journal = {Chemical Physics Letters},
volume = {240},
number = {1},
pages = {180--184},
publisher = {North-Holland},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
58.
Dos Santos, MC; Bolivar-Martinez, LE; Galvao, DS
Theoretical Study of Push-Pull Molecules Based on Thiophene Oligomers [2528-30] Journal Article
In: PROCEEDINGS-SPIE THE INTERNATIONAL SOCIETY FOR OPTICAL ENGINEERING, pp. 135–135, 1995.
BibTeX | Tags:
@article{dos1995theoretical,
title = {Theoretical Study of Push-Pull Molecules Based on Thiophene Oligomers [2528-30]},
author = {Dos Santos, MC and Bolivar-Martinez, LE and Galvao, DS},
year = {1995},
date = {1995-01-01},
journal = {PROCEEDINGS-SPIE THE INTERNATIONAL SOCIETY FOR OPTICAL ENGINEERING},
pages = {135--135},
publisher = {SPIE INTERNATIONAL SOCIETY FOR OPTICAL},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
1994
57.
Soos, Zolt'an G; Galv ao, Douglas S; Etemad, Shahab
Fluorescence and excited-state structure of conjugated polymers Journal Article
In: Advanced materials, vol. 6, no. 4, pp. 280–287, 1994.
BibTeX | Tags:
@article{soos1994fluorescence,
title = {Fluorescence and excited-state structure of conjugated polymers},
author = {Soos, Zolt'an G and Galv~ao, Douglas S and Etemad, Shahab},
year = {1994},
date = {1994-01-01},
journal = {Advanced materials},
volume = {6},
number = {4},
pages = {280--287},
publisher = {WILEY-VCH Verlag GmbH},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
56.
Lavarda, FC; Dos Santos, MC; Galv ao, DS; Laks, B
Near resonant scattering from nonsymmetric dimers: Applications to substituted polyanilines Journal Article
In: Physical review letters, vol. 73, no. 9, pp. 1267, 1994.
BibTeX | Tags:
@article{lavarda1994near,
title = {Near resonant scattering from nonsymmetric dimers: Applications to substituted polyanilines},
author = {Lavarda, FC and Dos Santos, MC and Galv~ao, DS and Laks, B},
year = {1994},
date = {1994-01-01},
journal = {Physical review letters},
volume = {73},
number = {9},
pages = {1267},
publisher = {American Physical Society},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
55.
Baughman, RH; Galvao, DS; Cui, C
Novel structures and properties of conjugated carbon phases with three-dimensional connectivity Proceedings Article
In: Science and Technology of Synthetic Metals, 1994. ICSM'94. International Conference on, pp. 446–446, IEEE 1994.
BibTeX | Tags:
@inproceedings{baughman1994novel,
title = {Novel structures and properties of conjugated carbon phases with three-dimensional connectivity},
author = {Baughman, RH and Galvao, DS and Cui, C},
year = {1994},
date = {1994-01-01},
booktitle = {Science and Technology of Synthetic Metals, 1994. ICSM'94. International Conference on},
pages = {446--446},
organization = {IEEE},
keywords = {},
pubstate = {published},
tppubtype = {inproceedings}
}
54.
Soos, ZG; Galvao, DS
One-and two-photon excitations of polythiophene: role of nonconjugated heteroatoms Journal Article
In: The Journal of Physical Chemistry, vol. 98, no. 3, pp. 1029–1033, 1994.
BibTeX | Tags:
@article{soos1994one,
title = {One-and two-photon excitations of polythiophene: role of nonconjugated heteroatoms},
author = {Soos, ZG and Galvao, DS},
year = {1994},
date = {1994-01-01},
journal = {The Journal of Physical Chemistry},
volume = {98},
number = {3},
pages = {1029--1033},
publisher = {ACS Publications},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
53.
Lavarda, FC; Dos Santos, MC; Galvao, DS; Laks, B
Insulator-to-metal transition in polythiophene Journal Article
In: Physical Review B, vol. 49, no. 2, pp. 979, 1994.
BibTeX | Tags:
@article{lavarda1994insulator,
title = {Insulator-to-metal transition in polythiophene},
author = {Lavarda, FC and Dos Santos, MC and Galvao, DS and Laks, B},
year = {1994},
date = {1994-01-01},
journal = {Physical Review B},
volume = {49},
number = {2},
pages = {979},
publisher = {APS},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
52.
Soos, Zoltan G; Galvao, Douglas S; Etemad, Shahab
Polymer fluorescence: even-parity states, alternation, and heteroatoms Proceedings Article
In: OE/LASE'94, pp. 115–126, International Society for Optics and Photonics 1994.
BibTeX | Tags:
@inproceedings{soos1994polymer,
title = {Polymer fluorescence: even-parity states, alternation, and heteroatoms},
author = {Soos, Zoltan G and Galvao, Douglas S and Etemad, Shahab},
year = {1994},
date = {1994-01-01},
booktitle = {OE/LASE'94},
pages = {115--126},
organization = {International Society for Optics and Photonics},
keywords = {},
pubstate = {published},
tppubtype = {inproceedings}
}
1993
51.
Baughman, RH; Galvao, DS
Crystalline networks with unusual predicted mechanical and thermal properties Journal Article
In: Nature, vol. 365, no. 6448, pp. 735–737, 1993.
Abstract | Links | BibTeX | Tags: top20
@article{baughman1993crystalline,
title = {Crystalline networks with unusual predicted mechanical and thermal properties},
author = {RH Baughman and DS Galvao},
url = {http://www.nature.com/nature/journal/v365/n6448/abs/365735a0.html},
doi = {10.1038/365735a0},
year = {1993},
date = {1993-01-01},
journal = {Nature},
volume = {365},
number = {6448},
pages = {735--737},
publisher = {Nature Publishing Group},
abstract = {Most materials shrink laterally and become less dense when stretched. Materials that both expand laterally (that is, have negative Poisson's ratio) and densify when stretched are of interest both from the fundamental and the practical points of view1–5. A few monocrystalline phases with negative Poisson's ratio are known3,4, but these do not densify when stretched. Here we present molecular-mechanics calculations for some hypothetical phases of carbon which exhibit both kinds of behaviour. The properties derive from the presence of bonds that act as hinges in extended helical chains. Other unusual properties of these phases include negative thermal expansion, dopant-controlled porosity and low-temperature polymorphism. Such structures can be envisaged for polyacetylene, polydiacetylene, polyphenylene and (BN)x phases, as well as for variants of some known, structurally related inorganic phases.},
keywords = {top20},
pubstate = {published},
tppubtype = {article}
}
Most materials shrink laterally and become less dense when stretched. Materials that both expand laterally (that is, have negative Poisson's ratio) and densify when stretched are of interest both from the fundamental and the practical points of view1–5. A few monocrystalline phases with negative Poisson's ratio are known3,4, but these do not densify when stretched. Here we present molecular-mechanics calculations for some hypothetical phases of carbon which exhibit both kinds of behaviour. The properties derive from the presence of bonds that act as hinges in extended helical chains. Other unusual properties of these phases include negative thermal expansion, dopant-controlled porosity and low-temperature polymorphism. Such structures can be envisaged for polyacetylene, polydiacetylene, polyphenylene and (BN)x phases, as well as for variants of some known, structurally related inorganic phases.
50.
S Ramasesha ZG Soos, DS Galvao
In: Physical Review Letters, vol. 71, no. 10, pp. 1609, 1993.
Abstract | Links | BibTeX | Tags: Molecular Dynamics
@article{soos1993band,
title = {Band to correlated crossover in alternating Hubbard and Pariser-Parr-Pople chains: Nature of the lowest singlet excitation of conjugated polymers},
author = {ZG Soos, S Ramasesha, DS Galvao},
url = {http://journals.aps.org/prl/abstract/10.1103/PhysRevLett.71.1609},
doi = {10.1103/PhysRevLett.71.1609},
year = {1993},
date = {1993-01-01},
journal = {Physical Review Letters},
volume = {71},
number = {10},
pages = {1609},
publisher = {American Physical Society},
abstract = {The evolution with increasing Coulomb correlations of a semiconductor to a magnetic insulator is related to an excited-state crossover in π-electron models for conjugated polymers. We associate strong fluorescence with a lowest singlet excitation S1 that is dipole allowed, on the band side, while S1 becomes two-photon allowed on the correlated side. S1/S2 crossovers in Hubbard, Pariser-Parr-Pople, or other chains with electron-hole symmetry and alternating transfer integrals t(1±δ) are based on exact results at δ=0 and 1, on molecular exciton theory at large δ, and on oligomer calculations up to twelve sites.},
keywords = {Molecular Dynamics},
pubstate = {published},
tppubtype = {article}
}
The evolution with increasing Coulomb correlations of a semiconductor to a magnetic insulator is related to an excited-state crossover in π-electron models for conjugated polymers. We associate strong fluorescence with a lowest singlet excitation S1 that is dipole allowed, on the band side, while S1 becomes two-photon allowed on the correlated side. S1/S2 crossovers in Hubbard, Pariser-Parr-Pople, or other chains with electron-hole symmetry and alternating transfer integrals t(1±δ) are based on exact results at δ=0 and 1, on molecular exciton theory at large δ, and on oligomer calculations up to twelve sites.
49.
Soos, ZG; Ramasesha, S; Galvao, DS; Etemad, S
Excitation and relaxation energies of trans-stilbene: Confined singlet, triplet, and charged bipolarons Journal Article
In: Physical Review B, vol. 47, no. 4, pp. 1742, 1993.
BibTeX | Tags:
@article{soos1993excitation,
title = {Excitation and relaxation energies of trans-stilbene: Confined singlet, triplet, and charged bipolarons},
author = {Soos, ZG and Ramasesha, S and Galvao, DS and Etemad, S},
year = {1993},
date = {1993-01-01},
journal = {Physical Review B},
volume = {47},
number = {4},
pages = {1742},
publisher = {APS},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
48.
Galvao, DS; Soos, ZG; Ramasesha, S; Etemad, S
A parametric method 3 (PM3) study of trans-stilbene Journal Article
In: The Journal of chemical physics, vol. 98, no. 4, pp. 3016–3021, 1993.
BibTeX | Tags:
@article{galvao1993parametric,
title = {A parametric method 3 (PM3) study of trans-stilbene},
author = {Galvao, DS and Soos, ZG and Ramasesha, S and Etemad, S},
year = {1993},
date = {1993-01-01},
journal = {The Journal of chemical physics},
volume = {98},
number = {4},
pages = {3016--3021},
publisher = {AIP Publishing},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
47.
Soos, Zoltan G; Galvao, Douglas S; Ramasesha, S; Etemad, Shahab
Photophysics of light-emitting conjugated polymers Proceedings Article
In: OE/LASE'93: Optics, Electro-Optics, & Laser Applications in Science& Engineering, pp. 274–284, International Society for Optics and Photonics 1993.
BibTeX | Tags:
@inproceedings{soos1993photophysicsb,
title = {Photophysics of light-emitting conjugated polymers},
author = {Soos, Zoltan G and Galvao, Douglas S and Ramasesha, S and Etemad, Shahab},
year = {1993},
date = {1993-01-01},
booktitle = {OE/LASE'93: Optics, Electro-Optics, & Laser Applications in Science& Engineering},
pages = {274--284},
organization = {International Society for Optics and Photonics},
keywords = {},
pubstate = {published},
tppubtype = {inproceedings}
}
46.
Baughman, Ray H; Galv ao, Douglas S; Cui, Changxing; Wang, Yang; Tom'anek, David
Fullereneynes: a new family of porous fullerenes Journal Article
In: Chemical physics letters, vol. 204, no. 1, pp. 8–14, 1993.
BibTeX | Tags:
@article{baughman1993fullereneynes,
title = {Fullereneynes: a new family of porous fullerenes},
author = {Baughman, Ray H and Galv~ao, Douglas S and Cui, Changxing and Wang, Yang and Tom'anek, David},
year = {1993},
date = {1993-01-01},
journal = {Chemical physics letters},
volume = {204},
number = {1},
pages = {8--14},
publisher = {North-Holland},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
45.
Soos, ZG; Ramasesha, S; Galvao, DS; Kepler, RG; Etemad, S
Electronic excitations and alternation of conjugated polymers Journal Article
In: Synthetic metals, vol. 54, no. 1, pp. 35–47, 1993.
BibTeX | Tags:
@article{soos1993electronic,
title = {Electronic excitations and alternation of conjugated polymers},
author = {Soos, ZG and Ramasesha, S and Galvao, DS and Kepler, RG and Etemad, S},
year = {1993},
date = {1993-01-01},
journal = {Synthetic metals},
volume = {54},
number = {1},
pages = {35--47},
publisher = {Elsevier},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
44.
Ramasesha, S; Galvao, DS; Soos, ZG
Exact eigenstates of the Pariser-Parr-Pople model for anthracene Journal Article
In: The Journal of Physical Chemistry, vol. 97, no. 12, pp. 2823–2829, 1993.
BibTeX | Tags:
@article{ramasesha1993exact,
title = {Exact eigenstates of the Pariser-Parr-Pople model for anthracene},
author = {Ramasesha, S and Galvao, DS and Soos, ZG},
year = {1993},
date = {1993-01-01},
journal = {The Journal of Physical Chemistry},
volume = {97},
number = {12},
pages = {2823--2829},
publisher = {ACS Publications},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
43.
Baughman, RH; Galvao, DS
Tubulanes: carbon phases based on cross-linked fullerene tubules Journal Article
In: Chemical physics letters, vol. 211, no. 1, pp. 110–118, 1993.
BibTeX | Tags:
@article{baughman1993tubulanes,
title = {Tubulanes: carbon phases based on cross-linked fullerene tubules},
author = {Baughman, RH and Galvao, DS},
year = {1993},
date = {1993-01-01},
journal = {Chemical physics letters},
volume = {211},
number = {1},
pages = {110--118},
publisher = {North-Holland},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
42.
Lavarda, FC; Dos Santos, MC; Galv ao, DS; Laks, B
Disordered distribution of defects in polythiophene Journal Article
In: Synthetic metals, vol. 57, no. 2, pp. 4499–4506, 1993.
BibTeX | Tags:
@article{lavarda1993disordered,
title = {Disordered distribution of defects in polythiophene},
author = {Lavarda, FC and Dos Santos, MC and Galv~ao, DS and Laks, B},
year = {1993},
date = {1993-01-01},
journal = {Synthetic metals},
volume = {57},
number = {2},
pages = {4499--4506},
publisher = {Elsevier},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
41.
Soos, ZG; Galvao, DS; Ramasesha, S; Etemad, S
Photophysics of light-emitting conjugated polymers (Invited Paper)[1852-33] Journal Article
In: PROCEEDINGS-SPIE THE INTERNATIONAL SOCIETY FOR OPTICAL ENGINEERING, pp. 274–274, 1993.
BibTeX | Tags:
@article{soos1993photophysics,
title = {Photophysics of light-emitting conjugated polymers (Invited Paper)[1852-33]},
author = {Soos, ZG and Galvao, DS and Ramasesha, S and Etemad, S},
year = {1993},
date = {1993-01-01},
journal = {PROCEEDINGS-SPIE THE INTERNATIONAL SOCIETY FOR OPTICAL ENGINEERING},
pages = {274--274},
publisher = {SPIE INTERNATIONAL SOCIETY FOR OPTICAL},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
40.
Soos, ZG; Galvao, DS; Etemad, S; Keplero, RG
Conjugated polymer fluorescence: Interplay of correlations and alternation Journal Article
In: MRS Proceedings, vol. 328, pp. 383, 1993.
BibTeX | Tags:
@article{soos1993conjugated,
title = {Conjugated polymer fluorescence: Interplay of correlations and alternation},
author = {Soos, ZG and Galvao, DS and Etemad, S and Keplero, RG},
year = {1993},
date = {1993-01-01},
journal = {MRS Proceedings},
volume = {328},
pages = {383},
publisher = {Cambridge University Press},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
39.
Laks, B; Dos Santos, DA; Galv ao, DS
Clustering effects in polyaniline chains Journal Article
In: Synthetic metals, vol. 57, no. 2, pp. 4507–4512, 1993.
BibTeX | Tags:
@article{laks1993clustering,
title = {Clustering effects in polyaniline chains},
author = {Laks, B and Dos Santos, DA and Galv~ao, DS},
year = {1993},
date = {1993-01-01},
journal = {Synthetic metals},
volume = {57},
number = {2},
pages = {4507--4512},
publisher = {Elsevier},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
1992
38.
Soos, ZG; Etemad, S; Galvao, DS; Ramasesha, S
Fluorescence and topological gap of conjugated phenylene polymers Journal Article
In: Chemical physics letters, vol. 194, no. 4, pp. 341–346, 1992.
BibTeX | Tags:
@article{soos1992fluorescence,
title = {Fluorescence and topological gap of conjugated phenylene polymers},
author = {Soos, ZG and Etemad, S and Galvao, DS and Ramasesha, S},
year = {1992},
date = {1992-01-01},
journal = {Chemical physics letters},
volume = {194},
number = {4},
pages = {341--346},
publisher = {North-Holland},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
37.
Dos Santos, DA; Galvao, DS; Laks, B; Dos Santos, MC
Poly (alkylthiophenes): chain conformation and thermochromism Journal Article
In: Synthetic metals, vol. 51, no. 1, pp. 203–209, 1992.
BibTeX | Tags:
@article{dos1992poly,
title = {Poly (alkylthiophenes): chain conformation and thermochromism},
author = {Dos Santos, DA and Galvao, DS and Laks, B and Dos Santos, MC},
year = {1992},
date = {1992-01-01},
journal = {Synthetic metals},
volume = {51},
number = {1},
pages = {203--209},
publisher = {Elsevier},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
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