Ordinary and rotatory intensities for X-ray absorption at the C-1s edge of organic chiral molecules, propylene oxide and trans-1,2-dimethylcyclopropane

The results of ab initio calculations with extended basis sets and full intrachannel coupling of core excited/ionized states of the chiral molecules trans-1,2-dimethylcyclopropane and propylene oxide are presented, The calculations are performed in the static-exchange approximation including electronic relaxation of the ion target state. Both oscillator strengths and rotatory strengths for X-ray absorption at the C-1s edge are obtained in an energy range covering discrete and continuum spectra up to 20 eV above the ionization threshold, The results show the importance of including the electronic relaxation in a description of the final states for the calculation of both excitation energies and the ordinary and rotatory intensities for the absorption of circularly polarized X-rays. (C) 1997 Published by Elsevier Science B.V.