Eur. Phys. J. D (2016) 70: 123
https://doi.org/10.1140/epjd/e2016-70153-2

Regular Article

Recent research directions in Fribourg: nuclear dynamics in resonances revealed by 2-dimensional EEL spectra, electron collisions with ionic liquids and electronic excitation of pyrimidine^*

¹ Department of Chemistry, University of Fribourg, chemin du Musée 9, 1700 Fribourg, Switzerland
² Department of Physical Sciences, The Open University, Walton Hall, Milton Keynes, MK7 6AA, UK
³ Max-Born Institute for Nonlinear Optics and Short Pulse Spectroscopy, Max-Born-Strasse 2A, 12489 Berlin, Germany
⁴ Mulliken Center for Theoretical Chemistry, Institut für Physikalische und Theoretische Chemie, Universität Bonn, Beringstrasse 4, 53115 Bonn, Germany

^a e-mail: michael.allan@unifr.ch

Received: 29 February 2016
Received in final form: 12 April 2016
Published online: 26 May 2016

Abstract

The article briefly reviews three subjects recently investigated in Fribourg: (i) electron collisions with surfaces of ionic liquids, (ii) two-dimensional (2D) electron energy loss spectra and (iii) resonances in absolute cross sections for electronic excitation of unsaturated compounds. Electron energy loss spectra of four ionic liquids revealed a number of excited states, including triplet states. A solution of a dye in an ionic liquid showed an energy-loss band of the solute, but not in all ionic liquids. 2D spectra reveal state-to-state information (given resonance to given final state) and are shown to be an interesting means to gain insight into dynamics of nuclear motion in resonances. Absolute cross sections for pyrimidine are reported as a function of scattering angle and as a function of electron energy. They reveal resonant structure which was reproduced very nicely by R-matrix calculations. The calculation provided an assignment of the resonances which reveals common patterns in compounds containing double bonds.