On the electronic structure of CNCl and NOCl

The ionization potentials and relative X-ray intensities were calculated for CNCl and NOCl by means of an ab initio LCAO SCF program. The data obtained are compared with the Cl Kβ spectra which were recorded using a high-resolution curved crystal spectrograph. The agreement between theory and experiment is satisfactory and allows for a reliable assignment of the prominent spectral features to the corresponding molecular X-ray transitions. A strong conjugation of the Cl lone pair electrons with the π bonds of the CN group has been found for CNCl. In the case of NOCl a corresponding conjugation of the Cl lone pair electrons with the double bonds of the NO group is absent.