Ab initio and density functional studies on the structure and vibrational Spectra of ۲-(۴-methyl-۲-biphenyl)-۴-amino-۱, ۲, ۴-triazole-۳-thiol

The molecular structure (bond distances and angles), dipole moment and vibrational spectroscopic data (vibrational frequencies, IR and Raman intensities) of ۲-(۴-methyl-۲-biphenyl)-۴-amino-۱, ۲, ۴-triazole-۳-thiol were calculated using Hartree–Fock (HF) and density functional (DFT) with basis sets ۶-۳۱G* and ۶- ۳۱+G*.This molecule was chosen as the model for the present study, because the synthesis and X-ray crystal structure analysis of a possible bioactive molecule, ۲-(۴-methyl-۲-biphenyl)-۴-amino-۱, ۲, ۴-triazole-۳ thiol have been reported. The theoretical results are discussed mainly in terms of comparisons with available experimental data. For geometric data, good agreement between theory and experiment is obtained for the HF and B۳LYP levels with basis sets including diffuse functions. The calculated vibrational spectra were interpreted and band assignments were reported. In addition, ۱H- and ۱۳C-nuclear magnetic shielding constants of this compound were calculated by employing the direct implementation of the gauge including-atomic-orbital (GIAO) method at the Hartree–Fock (HF) using ۶-۳۱G* basis set.

کلیدواژه ها:

DFT ، FT-IR spectrum ، HF ، Vibrational assignments ، ۱ ، ۲ ، ۴-Triazole