Density functional calculations Al-27 and N-14 quadrupole coupling constants in the H-capped (10, 0) and (4, 4) single-walled aluminum nitride nanotube

Density functional theory (DFT) calculations were performed to calculate nitrogen-14 and aluminum-27 quadrupole coupling constant in the representative considered models of zigzag and armchair aluminum nitride nanotubes (AlNNTs) for the first time. The considered models consisting of 1 nm length of H-capped (10, 0) and (4, 4) single-walled ANNT were first allowed to fully relax and then the CQ calculation were performed on the geometrically optimized models. The evaluated nuclear quadrupole coupling constant for the above-mentioned nuclei reveal that the considered models can be divided into four layers of nuclei with an equivalent electrostatic environment where those nuclei at the ends of tubes have a very strong electrostatic environment compared to the other nuclei along the length of tubes. Those nuclei at the center of the tube length also have an equivalent electrostatic environment. The calculations were performed based on the B3LYP DFT method and 6-31G∗ and 6-31++G∗∗ standard basis sets using the Gaussian 98 package of program.