Theoretical Study of the Correlation between 14N NQCC and Its Partial Atomic Charge in Amino Derivatives of Adamantane

The electronic structures and electrostatic potential of some amino derivatives of adamantane have been studied using density functional theory. The partial atomic charges and nuclear quadrupole coupling constants (NQCC) of 14N nucleus of the considered molecules have been reported. The partial atomic charges are calculated with two methods for 14N nucleus: Mulliken charges and natural bond orbital (NBO). All of the computations were carried out using the Gaussian 03 program at the B3LYP/6-311++G(d,p) level of theory. The results of both methods show reasonably good correlation with NQCC parameter, however, a much better correlation is found between NBO charges and NQCC of 14N nucleus.