A DFT study on carbon-doping at different sites of (8,0) boron nitride nanotube

A density functional theory study is carried out to investigate the geometries and electronic structure of pristine and carbon-doped (8, 0) single-walled boron nitride nanotubes (BNNTs). In order to understand the effect of impurities or doping on (8, 0) single-walled BNNT, we simulated C-doping in six different ways. Geometry optimizations reveal that in the considered models, B-N bond lengths are not significantly influenced by C-doping. Based on the quantum theory of atoms in molecules analysis, charge density accumulation for axial B-N bond critical points (BCPs) of pristine BNNT is slightly larger than zigzag ones. However, due to C-doping at the B- or N-tips, the evaluated electron density tends to decrease slightly at both axial and zigzag B-N BCPs. Besides, results indicate that influence of C-doping on properties of the (8, 0) BNNT could be also detected by values of chemical shielding isotropy (sigma (iso)) and anisotropy (Delta sigma).