Emitter-site selective photoelectron circular dichroism of trifluoromethyloxirane

M. Ilchen; G. Hartmann; P. Rupprecht; A. N. Artemyev; R. N. Coffee; Z. Li; H. Ohldag; H. Ogasawara; T. Osipov; D. Ray; Ph. Schmidt; T. J. A. Wolf; A. Ehresmann; S. Moeller; A. Knie; Ph. V. Demekhin

doi:10.1103/physreva.95.053423

arXiv · 1704.02265

Emitter-site selective photoelectron circular dichroism of trifluoromethyloxirane

M. Ilchen·G. Hartmann·P. Rupprecht·A. N. Artemyev·R. N. Coffee·Z. Li·H. Ohldag·H. Ogasawara·T. Osipov·D. Ray·Ph. Schmidt·T. J. A. Wolf·A. Ehresmann·S. Moeller·A. Knie·Ph. V. Demekhin

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Abstract

The angle-resolved inner-shell photoionization of R-trifluoromethyloxirane, C3H3F3O, is studied experimentally and theoretically. Thereby, we investigate the photoelectron circular dichroism (PECD) for nearly-symmetric O 1s and F 1s electronic orbitals, which are localized on different molecular sites. The respective dichroic $\beta_{1}$ and angular distribution $\beta_{2}$ parameters are measured at the photoelectron kinetic energies from 1 to 16 eV by using variably polarized synchrotron radiation and velocity map imaging spectroscopy. The present experimental results are in good agreement with the outcome of ab initio electronic structure calculations. We report a sizable chiral asymmetry $\beta_{1}$ of up to about 9% for the K-shell photoionization of oxygen atom. For the individual fluorine atoms, the present calculations predict asymmetries of similar size. However, being averaged over all fluorine atoms, it drops down to about 2%, as also observed in the present experiment. Our study demonstrates a strong emitter- and site-sensitivity of PECD in the one-photon inner-shell ionization of this chiral molecule.

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M. Ilchen, G. Hartmann, P. Rupprecht, A. N. Artemyev, R. N. Coffee, Z. Li, H. Ohldag, H. Ogasawara, T. Osipov, D. Ray, Ph. Schmidt, T. J. A. Wolf, A. Ehresmann, S. Moeller, A. Knie, Ph. V. Demekhin. 2017-04-07. Emitter-site selective photoelectron circular dichroism of trifluoromethyloxirane. https://doi.org/10.1103/physreva.95.053423

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