Conformational and nuclear dynamics effects in molecular Auger spectra: Fluorine core hole decay in CF4
نویسندگان
چکیده
In a molecular Auger spectrum information on the decaying state is implicitly ensemble-averaged. For a repulsive core-ionized state, for example, contributions from all parts of its potential curve are superimposed in the Auger spectrum. Using carbon tetrafluoride (CF4, tetrafluoromethane), we demonstrate for the first time that these contributions can be disentangled by recording photoelectronAuger electron coincidence spectra with high energy resolution. For the F K-VV spectrum of CF4, there are significant differences in the Auger decay at different intermediate state (single core hole) geometries. With the help of calculations, we show that these differences result primarily from zero-point-fluctuations in the neutral molecular ground state, but are amplified by the nuclear dynamics during Auger decay. PACS numbers: 07.81.+a, 07.85.Qe, 32.80.Hd, 33.80.Eh ‡ Present address: Institut für Experimentalphysik, Universität Hamburg, Luruper Chaussee 149, 22761 Hamburg, Germany
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