New assignment of 14N NQR spectral lines for tetrazoles derivatives

Abstract

In recent years, considerable interest has been shown in the study of tetrazole derivatives, which attract attention as highly nitrogenous compounds for use as an isosteric substitutes for various functional groups that leads to creation of novel biologically active substances. NQR techniques, being sensitive to the local environment of N-14 nuclei, provide great opportunities to study these new substances. To make investigation of complex compounds containing tetrazoles derivatives easier and more reliable a correctly assigned N-14 NQR spectra of tetrazoles are required. Here we report on the results of our DFT B3LYP calculations of N-14 NQR spectral parameters (quadrupole coupling constant Qcc and the asymmetry parameter of the electric field gradient g) for tetrazole, 5-aminotetrazole and 5-aminotetrazole monohydrate. It has been found that the commonly accepted assignment of the N-14 NQR spectral lines for these molecules is incorrect. A new assignment for these molecules is proposed. (C) 2018 Elsevier B.V. All rights reserved.