Calculation on the Electronic States of the Acrolein Molecule by the Semi-Empirical Molecular Orbital Method

It was found that the semi-empirical method proposed by Pariser and Parr can be applied to the n–π* transition as well as the π–π* transition in acrolein. In acrolein the (n, π*) triplet state is the lowest state. A weak band in the red side of the 0–0 band is a hot band and it is not the n–π* singlet-triplet transition band. The n–π* triplet band anticipated from calculation could not be found.