Effect of CH3CO functional group on the molecular and electronic properties of BN43zz nanotube: A computational chemistry study

The geometric and electronic structures of the CH3CO functionalized BN43 zigzag nanotube (BN43zz NT) were studied by means of the B3LYP hybrid density functional method using 6-31G(d) basis set. The position of CH3CO molecule on top of tube plays an important role on the tube-CH3CO interaction. Two types functionalized BN43zz NTs were found in interaction between CH3CO and BN43zz NT. It is energetically favorable for the CH3CO radical to interact with the slanted B-N bonds (in S type complexes with stronger adsorption energy) which are perpendicular to the tube axis. The more stable functionalized BN43zz NTs prefer open structure rather than closed four-membered-ring one. The HOMO-LUMO gap, electronic chemical potential μ, hardness η, softness S and electrophilicity index ω for CH3CO, BNNT and different configurations of functionalized BNNT in gas and polar solvent phases were calculated. These results show that the functionalization of BN43zz NT results in significant changes in the electronic properties of BNNTs. It is predicted that the conductivity of the nanotube increases upon adsorption of the CH3CO molecule on the tube. To gain a deep understanding of the electron delocalization in complexes, nucleus-independent chemical shift (NICS) analysis have been performed at B3LYP/6-31G(d) level using GIAO method. The results obtained by natural bond orbital (NBO) analysis showed that in the S and P complexes charge transfer occurs from BNNT to CH3CO and vice versa, respectively. Theory of atoms in molecules (AIM) was also applied to characterize B-O and N-C bonds in nanotubes.