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Updated: Jun 22, 2026

Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
Rotational dynamics and coupling of methyl group rotations in methyl fluoride studied by high resolution inelastic
O Kirstein1, M Prager, G J Schneider
1Australian Nuclear Science and Technology Organisation, The Bragg Institute, Lucas Heights, New South Wales 2234, Australia. oliver.kirstein@ansto.gov.au
Abstract:
Methyl group rotations in methyl fluoride were studied using the high flux backscattering spectrometer SPHERES at FRM-II. The asymmetry and width of the low temperature tunneling peak was used to determine if coupled rotations between neighboring methyl fluoride molecules exist. The temperature dependent broadening of the tunneling peak was used to determine the first librational transition and compared to the temperature dependent shift of the position of the tunneling peak. The results obtained by using inelastic neutron scattering confirm previous models that assume rotational coupling. This is the first neutron backscattering experiment with sub-microeV resolution at energy transfers up to 31 microeV.
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