Inner shell spectroscopy of the carbon—sulfur bond

The oscillator strengths for S 1s excitation of thiols (CH3SH, C2H5SH, C6H5SH) and thioethers (CH3SCH3, C2H5SC2H5 and C6H5SCH3) have been derived from ionization yield spectra recorded by synchrotron radiation. These spectra have been analyzed by comparison among the series. The discrete regions of each spectrum are dominated by a feature attributed to S 1s→σ*(SC) transitions. An S 1s→σ*(SH) transition has been identified in the thiol spectra by comparison of the RSH and RSR′ spectra. In addition, the C 1s, S 2p and S 2s oscillator strength spectra of CH3SH have been derived from electron energy loss spectra recorded under scattering conditions dominated by electric dipole transitions. The term value for the (C 1s−1, σ* (SC)) state in CH3SH is significantly smaller than that for the σ*(SC) resonances in the S 2p, S 2s and S 1s spectra, indicating a large site dependence of the core hole relaxation.