Molecular structure and vibrational spectra of 1,2-bis(4-pyridyl) ethane by density functional theory and ab initio Hartree-Fock calculations

The molecular geometry and vibrational frequencies of 1,2-bis(4-pyridyl) ethane (bpa) in the ground state have been calculated using the Hartree-Fock and density functional methods (B3LYP and BLYP) with 6-31G (d) basis set. The optimized geometric bond lengths obtained by using HF and bond angles obtained by DFT (BLYP) show the best agreement with the experimental values. Comparison of the observed fundamental vibrational frequencies of bpa and calculated results by density functional B3LYP. BLYP and Hartree-Fock methods indicates B3LYP is superior to the scaled Hartree-Fock and BLYP approach for molecular vibrational problems. (C) 2003 Elsevier Science B.V. All rights reserved.