Lifetime-vibrational interference effects in the ultra-soft x-ray emission spectrum of CO

Abstract
The effect of lifetime-vibrational interference in the carbon and oxygen ultra-soft x-ray emission (USX) spectra of CO is theoretically analyzed. Computed spectral functions are compared with high-resolution experimental recordings. A time dependent Franck–Condon formalism is employed in the theoretical treatment of the interference. The electronic states involved in the analysis are determined by means of large scale MCSCF and CI calculations and the nuclear wave functions are solved for numerically. Certain features of the spectra are found to be sensitively dependent on the interference and can hence be used as a monitor for the core state lifetime.