investigating the effects of molecular oxygen impurity on the quadrupole coupling constants of boron nitride nanotubes: computational studies

density functional theory (dft) calculations have been performed to investigating the effects of themolecular oxygen impurity on the quadrupole coupling constant (qcc) parameters of armchair and zigzagboron nitride nanotubes (bnnts). optimization processes have been performed to relax the original andimpure structures of the investigated bnnts. afterwards, the qcc parameters have been evaluated forthe boron and nitrogen atoms of the optimized bnnts. the results have indicated that the qccparameters of boron and nitrogen atoms could detect the effects of oxygen impurity in the structure ofbnnts, in which the changes of those nitrogen atoms dose to the impure region are more obvious. theb3lyp and b3pw91 exchange-correlation functional methods and the 6-31g* standard basis set asimplemented in the gaussian 98 package have been employed for performing the calculations.