Theoretical study of the U.V. spectrum of acetylene ii. Ab initio treatment of the renner-teller effect in 1¹Π<inf>u</inf> and 1¹Δ<inf>g</inf> electronic states

Abstract

A method for the treatment of the Renner-Teller effect in Π and Δ electronic states of tetraatomic molecules is developed. It is based on a matrix representation of the vibronic hamiltonian in a basis consisting of products of electronic wavefunctions and the eigenfunctions of two two-dimensional harmonic oscillators. The method is used for calculation of the vibronic structure of the 11Πu and the 11Δg electronic states of acetylene, whereby ab initio CI potential surfaces are employed. © 1985 Taylor & Francis Group, LLC.