L. Ould-moussa et al., Ab initio and density functional study of the geometrical, electronic and vibrational properties of 2,2 '-bipyridine, J RAMAN SP, 31(5), 2000, pp. 377-390
The conventional ab initio method at the closed restricted Hartree-Fock lev
el (RHF) and the Density Functional Theory (DFT) approach at the B3-LYP lev
el, using the 6-31G(+*) basis set, are applied to predict the molecular str
ucture and the energetic and vibrational properties (harmonic wavenumbers,
force fields and potential energy distributions) of five isotopomers of the
neutral molecule 2,2'-bipyridine (22BPY), The theoretical results are comp
ared to the Raman and infrared vibrational data. Using both methods, there
is a very good agreement between theory and experiment concerning not only
the absolute wavenumbers, but also the isotopic shifts. This accordance all
ows us to validate the calculated structure of 22BPY, The neutral molecule
22BPY is characterized by an aromatic structure in which two pyridyl rings
are linked by a single bond in a trans-planar conformation. From a methodol
ogical point of view, the B3-LYP method predicts more accurate structures a
nd harmonic vibrational wavenumbers than the RHF method. Copyright (C) 2000
John Wiley & Sons, Ltd.