Theoretical Analysis of Vibrational Spectra and Scaling-Factor of 2-Aryl-1,3,4-Oxadiazole Derivatives

Abstract

In this study, the direct molecular structure implementations for calculating vibrational spectra and scaling factors, and infrared intensities at both the Hartree-Fock (HF) and density functional (B3LYP) levels of theory with 6-31G(d), 6-311G(d), 6-31++G(d,p), and 6-311++G(d,p) basis sets are presented. Also, vibrational frequencies have been investigated as dependence on the choice of method and basis set. The parameters of molecular geometry and vibrational frequencies values of 2-aryl-1,3,4-oxadiazoles 5a-g in the ground state have been calculated. Theoretical determination of vibrational frequencies is quite useful both in understanding the relationship between the molecular structures and scaling factor. The data of 2-aryl-1,3,4-oxadiazoles 5a-g display significant electronic properties provide the basis for future design of efficient materials having the oxadiazole core and theoretical IR Studies. (C) 2008 Wiley Periodicals, Inc. Int J Quantum Chem 109: 328-341, 2009