Valence Electron Structure of the SF₆ and CS₂ Molecules, Studied in High Resolution X-ray Emission

Sulphur L, fluorine K and carbon K X-ray emission spectra from the molecules SF₆ and CS₂ are recorded with high resolution in a grazing incidence spectrometer. Apart from transitions between atomic core electron orbitals and molecular valence electron orbitals we observe in both molecules a group of very narrow (∼ 30 meV) lines. These lines are attributed to transitions in charged atomic sulphur fragments. From the SF₆ sulphur spectrum the following two conclusions are drawn:(1) It is necessary to include the 3d orbitals in the LCAO description of the valence electron structure and chemical bonding in the SF₆ molecule.(2) The one-center intensity model does not work satisfactorily for L-emission.