Excited state assignment and state-resolved photoelectron circular dichroism in chalcogen-substituted fenchones

Sudheendran Vasudevan; Steffen M. Giesen; Simon T. Ranecky; Lutz Marder; Igor Vidanović; Manjinder Kour; Catmarna Küstner-Wetekam; Nicolas Ladda; Sagnik Das; Tonio Rosen; Vidana Popkova; Hangyeol Lee; Denis Kargin; Tim Schäfer; Andreas Hans; Thomas Baumert; Robert Berger; Hendrike Braun; Arno Ehresmann; Guido W. Fuchs; Thomas F. Giesen; Jochen Mikosch; Rudolf Pietschnig; Arne Senftleben

arXiv · 2503.14261

Excited state assignment and state-resolved photoelectron circular dichroism in chalcogen-substituted fenchones

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Abstract

Excited electronic states of fenchone, thiofenchone, and selenofenchone are characterized and assigned with different gas-phase spectroscopic methods and \textit{ab initio} quantum chemical calculations. With an increasing atomic number of the chalcogen, we observe increasing bathochromic (red) shifts, which vary in strength for Rydberg states, valence-excited states, and ionization energies. The spectroscopic insight is used to state-resolve the contributions in multi-photon photoelectron circular dichroism with femtosecond laser pulses. This is shown to be a sensitive observable of molecular chirality in all studied chalcogenofenchones. Our work contributes new spectroscopic information, particularly on thiofenchone and selenofenchone. It may open a perspective for future coherent control experiments exploiting resonances in the visible and or near-ultraviolet spectral regions.

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Sudheendran Vasudevan, Steffen M. Giesen, Simon T. Ranecky, Lutz Marder, Igor Vidanović, Manjinder Kour, Catmarna Küstner-Wetekam, Nicolas Ladda, Sagnik Das, Tonio Rosen, Vidana Popkova, Hangyeol Lee, Denis Kargin, Tim Schäfer, Andreas Hans, Thomas Baumert, Robert Berger, Hendrike Braun, Arno Ehresmann, Guido W. Fuchs, Thomas F. Giesen, Jochen Mikosch, Rudolf Pietschnig, Arne Senftleben. 2025-03-18. Excited state assignment and state-resolved photoelectron circular dichroism in chalcogen-substituted fenchones. https://arxiv.org/abs/2503.14261

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