Doppler effect in resonant excitation of CF3SF5 probed by Auger electron spectroscopy

Ibuki Toshio

Itoh Shin-ichi

Tamenori Yusuke

Okada Kazumasa

Nagaoka Shin-ichi

Morishita Yuichiro

Suzuki Isao H.

Journal of Electron Spectroscopy and Related Phenomena

Atomiclike Auger electron emission was observed in resonant excitation of F1s electron into the σ*CSF molecular orbital of CF3SF5. This finding means that an S-F bond forming the C-S-F linear skeleton in the ground state dissociates in the order of femto-seconds. The Auger electron emitted from the F atom showed a Doppler shift by using angle-resolved photoelectron spectroscopy. Asymmetry parameter for the leaving F atom relative to the linearly polarized electric vector was deduced to be β = 1.9 at high photon energy of 688.7 eV and a value of β = 1.1 by detuning the photon energy down to 686.8 eV. The variation of β on the exciting energies projects a profile that an axial recoil approximation effectively works for the ultrafast S-F dissociation when the F1s-1σ*CSF state is generated at high energy level on the σ*CSF potential curve but retardation effects between the F and CF3SF4 fragments become noticeable at low energy level where kinetic energy of the F atom gets smaller.

K-shell excitation

Ultrafast dissociation

Auger electron spectroscopy

Asymmetry parameter

Chemistry [ 430 ]

eng

Elsevier Science B.V.

Copyright (c) 2006 Elsevier B.V.

[ISSN] 0368-2048

[DOI] 10.1016/j.elspec.2006.10.010

[NCID] AA00697082

[DOI] http://dx.doi.org/10.1016/j.elspec.2006.10.010