Université de Fribourg

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

Allan, Michael ; Regeta, Khrystyna ; Gorfinkiel, Jimena D. ; Mašín, Zdeněk ; Grimme, Stefan ; Bannwarth, Christoph

In: The European Physical Journal D, 2016, vol. 70, no. 5, p. 1–7

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...

Université de Fribourg

Theoretical study of the stacking behavior of selected polycondensed aromatic hydrocarbons with various symmetries

Antony, Jens ; Alameddine, Bassam ; Jenny, Titus A. ; Grimme, Stefan

In: The Journal of Physical Chemistry A, 2012, vol. 117, no. 3, p. 616–625

Stacked dimers of four polycondensed aromatic hydrocarbons, with structures varying from high to reduced symmetries, have been calculated with dispersion-corrected density functional theory. The configurations of the stacked dimers are readily classified by two in-plane displacements and a relative rotation. The potential energy surface in these three coordinates was calculated with rigid...

Université de Fribourg

Free electrons and ionic liquids: study of excited states by means of electron-energy loss spectroscopy and the density functional theory multireference configuration interaction method

Regeta, Khrystyna ; Bannwarth, Christoph ; Grimme, Stefan ; Allan, Michael

In: Physical Chemistry Chemical Physics, 2015, p. -

The technique of low energy (0–30 eV) electron impact spectroscopy, originally developed for gas phase molecules, is applied to room temperature ionic liquids (IL). Electron energy loss (EEL) spectra recorded near threshold, by collecting 0–2 eV electrons, are largely continuous, assigned to excitation of a quasi-continuum of high overtones and combination vibrations of low-frequency modes....