Spectrum and polarizability of polyphenyls in the Pariser-Parr-Pople approximation

The Pariser-Parr-Pople approximation is used to calculate the electronic structure, electronic absorption spectrum, and polarizability for biphenyl, terphenyl, and quaterphenyl. The self-consistent MO are taken as basis functions for the multiconfiguration approximation. The minimum number of singly excited configurations is included. Bond orders, bond lengths, transition energies, oscillator strengths, and wave functions of the excited states are given in that approximation. The results are compared with published data and, where possible, with experiment. Calculation of the -electron polarizability with allowance for configuration interaction is discussed. The agreement with experiment is satisfactory for all the characteristics calculated.