Université de Fribourg

Electron impact excitation of methane: determination of appearance energies for dissociation products

Danko, M. ; Orszagh, J. ; Ďurian, M. ; Kočišek, J. ; Daxner, M. ; Zöttl, S. ; Maljković, J. B. ; Fedor, Juraj ; Scheier, P. ; Denifl, S. ; Matejčík, Š.

In: Journal of Physics B: Atomic, Molecular and Optical Physics, 2013, vol. 46, no. 4, p. 045203

In this work, we present an experimental study of dissociative excitation of CH₄ utilizing a crossed electron molecular beam experiment. Methane was excited by nearly monochromatic electrons generated by a trochoidal electron monochromator. The dissociative products were identified on the basis of the emission spectra in the ultraviolet–visible (UV/VIS) spectral range. The excitation...

Université de Fribourg

On the role of the II(1/2g) state in spontaneous dissociation of krypton and xenon dimer ions

Fedor, Juraj ; Echt, O. ; Głuch, K. ; Matt-Leubner, S. ; Scheier, P. ; Märk, T.D.

In: Chemical Physics Letters, 2007, vol. 437, no. 4-6, p. 183-188

We have measured kinetic-energy-release distributions (KERD) for spontaneous dissociation of electronically excited dimer ions of krypton and xenon, formed by electron impact ionization of neutral precursors. The data cannot be reconciled by decay of the strongly bound II(1/2u) state that successfully explains dissociation of and Ne₂⁺ and Ar₂⁺. Instead, the KERD is dominated by...

Université de Fribourg

Dissociative electron attachment to HBr: A temperature effect

Fedor, Juraj ; Cingel, M. ; Skalný, J. D. ; Scheier, P. ; Märk, T. D. ; Čížek, M. ; Kolorenč, P. ; Horáček, J.

In: Physical Review A, 2007, vol. 75, p. 022703

The effects of rovibrational temperature on dissociative electron attachment to hydrogen bromide has been investigated from the experimental and theoretical point of view. Theoretical calculations based on the nonlocal resonance model predict a strong temperature effect on the Br⁻ fragment ion yield due to population of higher vibrational and rotational states. A crossed beam experimental setup...