The influence of NH 3-attaching on the NMR and NQR parameters in the (6,0) zigzag single-walled BPNTs: a density functional study

Abstract

The structural properties, NMR and NQR parameters in the pristine and NH 3-attached (6,0) zigzag BPNTs model were calculated using DFT methods in order to evaluate the influence of NH 3-attached on the (6,0) zigzag BPNTs for the first time. Geometry optimizations were carried out at the BLYP, B3LYP/6-31G * levels of theory using the Gaussian 03 program suites. The chemical shielding (CS) parameters for the sites of various 11B and 31P atoms and quadrupole coupling constant ( C Q ), and asymmetry parameter ( η Q ) at the sites of various 11B nuclei were calculated in the pristine and the NH 3-attached (6,0) zigzag BPNTs model. The values of dipole moments detect notable changes due to direct effect of the NH 3-attached on the BPNTs; however, the tip diameters are slightly significant changed in comparison to the pristine models and the gap energies of the NH 3-attached BPNT do not detect any changes in comparison to the pristine model. For the NH 3-attached BPNT, the NMR values for the 11B 14 atom which is directly bonded to the NH 3 molecule and the 31P atoms that directly bonded to the 11B 14 atom in the BPNT are significantly changed. CS I parameters of the atoms are increased whereas CS A parameters of the atoms are decreased. The NQR results showed that in BPNTs, the B atoms at the edges of nanotubes play dominant roles in determining the electronic behaviors of BPNTs and the average value of C Q ( 11B) and η Q for the NH 3-attached (6,0) zigzag BPNTs is further in comparison to the pristine model.