A New Method for Conformational Analysis by Photoelectron Spectroscopy with Application to Alkyl-substituted Styrenes

Abstract

Abstract A new method for molecular conformational analysis using photoelectron spectral data was developed and applied to alkyl-substituted styrenes as an example. The dihedral angle between the phenyl ring and the olefinic group planes, θ, in each molecule is evaluated by comparing the observed difference between the first and the third vertical ionization energies, ΔEiv1.3, with the empirically estimated ΔEiv1.3 vs. θ curve, the alkyl substituent effect being taken into account by the first order perturbation theory. The new method gives reasonable results consistent qualitatively with those given by other former methods.