Edge-termination and core-modification effects of hexagonal nanosheet graphene.

ABSTRACT: Optimized geometries and electronic structures of two different hexagonal grapheme nanosheets (HGNSs), with armchair (n-A-HGNS, n = 3-11) and zigzag (n-Z-HGNS, n = 1-8) edges have been calculated by using the GGA/PBE method implemented in the SIESTA package, with the DZP basis set, where n represents the number of peripheral rings. The computed HOMO-LUMO energy gap (Eg = ELUMO - EHOMO) decreases for fully H-terminated A- and Z-HGNSs with increasing n, i.e., with increasing nanosheet size and pπ-orbitals being widely delocalized over the sheet surface. The full terminations, calculated with various functional groups, including the electron-withdrawing (F-, Cl-, and CN-) and -donating (OH-, and SH-) substitutions, were addressed. Significant lowering of EHOMO and ELUMO was obtained for CN-te

SUBMITTER: Deng JP 

PROVIDER: S-EPMC6271332 | biostudies-literature | 2014 Feb

REPOSITORIES: biostudies-literature