High resolution inner-shell spectroscopy and ab initio CI calculations on TiCl4 and isoelectronic molecules

Inner-shell excitation spectra of gas phase TiCl4, VOCl3 and CrO2Cl2 have been recorded in the Cl 2p and O 1s edge regions. The assignment of the core excitations is based on ab initio calculations in the relaxed 1h-1p CI scheme. The computational approach has provided excitation energy patterns and photoabsorption oscillator strengths in satisfactory agreement with the experimental spectra, indicating the reliability of the theoretical model. The calculations are extended also to the compound MnO3Cl and to the Cl 1s core excitation spectra of the whole series of molecules. The interpretation of the final excited states in terms of orbital composition is also discussed as well as the spectral variations along the series with the progressive substitution of the chlorine atom with the oxygen atom.