VIBRATIONAL ANALYSIS OF THE RADICAL-ANION AND CATION OF BIPHENYL BASED ON DENSITY-FUNCTIONAL CALCULATIONS

The density functional theory has been used for calculating the struct ures and vibrational wavenumbers of the radical anion and cation of bi phenyl. The radical anion has a planar structure, while the radical ca tion is twisted. Upon ionization, structural changes occur in the dire ction from benzenoid to quinoid. Unsealed wavenumbers calculated at th e Becke-Lee-Yang-Parr/6-31G level are mostly in agreement with observ ed vibrational wavenumbers in the literature.