¹²⁹Xe nuclear resonance scattering on solid Xe and ¹²⁹Xe clathrate hydrate

¹ Jülich Centre for Neutron Science JCNS and Peter Grünberg Institute PGI, JARA - FIT, Forschungszentrum Jülich GmbH - D-52425 Jülich, Germany, EU
² Institut des Sciences Moléculaires, CNRS, Université de Bordeaux 1 - F-33405 TALENCE Cedex, France, EU
³ Jülich Centre for Neutron Science, JCNS, Forschungszentrum Jülich GmbH - Outstation at ILL, BP 156, 38042 Grenoble, France, EU
⁴ Faculté des Sciences, Université de Liège - B-4000 Liège, Belgium, EU

Received: 25 May 2013
Accepted: 25 July 2013

Abstract

Nuclear inelastic and nuclear forward-scattering experiments utilizing the ¹²⁹Xe Mössbauer resonance were performed on solid Xe and enriched ¹²⁹Xe clathrate hydrate. The lifetime and energy of the nuclear resonance were determined to be and , respectively. Nuclear inelastic scattering spectra could be obtained with an instrumental resolution of . Despite low Lamb-Mössbauer factors, Xe specific densities of phonon states were derived for solid Xe and Xe clathrate hydrate. Their reliability was investigated using 1-phonon terms obtained by fixing Lamb-Mössbauer factor values within the applied Fourier-Log decomposition. ABINIT calculations of the density of phonon states in solid Xe supplement the interpretation of the experimental data for fcc Xe and good agreement with published densities of phonon states could be achieved below . Results for the Xe clathrate hydrate essentially confirm the rattling nature of the Xe guests and indicate that Xe modes do not contribute to lattice dynamics above .