%0 Journal Article %1 WOS:000265281700077 %A Caetano, E W S %A Freire, V N %A dos Santos, S G %A Albuquerque, E L %A Galvao, D S %A Sato, F %C 1155 16TH ST, NW, WASHINGTON, DC 20036 USA %D 2009 %I AMER CHEMICAL SOC %J LANGMUIR %K imported %N 8 %P 4751-4758 %R 10.1021/la803929f %T Defects in Graphene-Based Twisted Nanoribbons: Structural, Electronic, and Optical Properties %V 25 %X We present some computational simulations of graphene-based nanoribbons with a number of half-twists varying from 0 to 4 and two types of defects obtained by removing a single carbon atom from two different sites. Optimized geometries are found by using a mix of classical quantum semiempirical computations. According with the simulations results, the local curvature of the nanoribbons increases at the defect sites, especially fora higher number of half-twists. The HOMO-LUMO energy gap of the nanostructures has significant variation when the number of half-twists increases for the defective nanoribbons. At the quantum semiempirical level, the first optically active transitions and oscillator strengths are calculated using the full configuration interaction (CI) framework, and the optical absorption in the UV/vis range (electronic transitions) and in the infrared (vibrational transitions) are achieved. Distinct nanoribbons show unique spectral signatures in the UV/vis range, with the first absorption peaks in wavelengths ranging from the orange to the violet. Strong absorption is observed in the ultraviolet region, although differences in their infrared spectra are hardly discernible.

@article{WOS:000265281700077, abstract = {We present some computational simulations of graphene-based nanoribbons with a number of half-twists varying from 0 to 4 and two types of defects obtained by removing a single carbon atom from two different sites. Optimized geometries are found by using a mix of classical quantum semiempirical computations. According with the simulations results, the local curvature of the nanoribbons increases at the defect sites, especially fora higher number of half-twists. The HOMO-LUMO energy gap of the nanostructures has significant variation when the number of half-twists increases for the defective nanoribbons. At the quantum semiempirical level, the first optically active transitions and oscillator strengths are calculated using the full configuration interaction (CI) framework, and the optical absorption in the UV/vis range (electronic transitions) and in the infrared (vibrational transitions) are achieved. Distinct nanoribbons show unique spectral signatures in the UV/vis range, with the first absorption peaks in wavelengths ranging from the orange to the violet. Strong absorption is observed in the ultraviolet region, although differences in their infrared spectra are hardly discernible.}, added-at = {2022-05-23T20:00:14.000+0200}, address = {1155 16TH ST, NW, WASHINGTON, DC 20036 USA}, author = {Caetano, E W S and Freire, V N and dos Santos, S G and Albuquerque, E L and Galvao, D S and Sato, F}, biburl = {https://www.bibsonomy.org/bibtex/2078379c8aa85b54384ba7d9d8ce3ad75/ppgfis_ufc_br}, doi = {10.1021/la803929f}, interhash = {65f2c30e375a376ab252f40cbb124fbf}, intrahash = {078379c8aa85b54384ba7d9d8ce3ad75}, issn = {0743-7463}, journal = {LANGMUIR}, keywords = {imported}, number = 8, pages = {4751-4758}, publisher = {AMER CHEMICAL SOC}, pubstate = {published}, timestamp = {2022-05-23T20:00:14.000+0200}, title = {Defects in Graphene-Based Twisted Nanoribbons: Structural, Electronic, and Optical Properties}, tppubtype = {article}, volume = 25, year = 2009 }