S 1←S 0 vibronic spectra and inversion potentials in theS 1 states of acetyl and formyl halides

Abstract

The potential functions of inversion in the S1 states are determined from the inversion transitions (out-of-plane C=O vibrations) found in the S1←S0 vibronic spectra of acetyl halide molecules. The high intensities of the hot inversion transitions are explained by the high probabilities of these transitions. The literature values of the inversion potentials (equilibrium values of angles formed by the C=O bonds deviating from the planes) of formyl halide molecules in the S1 states are refined. The inversion potentials of formyl and acetyl halides are similar.