The existence of an orientationally disordered cubic phase of solid ethanol is revealed by x-ray diffraction and Raman spectroscopic measurements. Such a phase, whose existence was postulated some time ago on the basis of specific-heat measurements, is produced by quenching below some 95 K a plastic crystal formed upon melting and subsequent...
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May 8, 2017 (v1)PublicationUploaded on: March 27, 2023
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June 7, 2022 (v1)Publication
The collective dynamics of liquid methanol‐d4 is studied by means of molecular‐dynamics simulation. The model potential is validated by means of lattice energy calculations and shows a very good agreement with the experimentally obtained crystal structure. Center‐of‐mass density and momentum fluctuations are investigated in the (Q,ω) region...
Uploaded on: March 25, 2023 -
April 20, 2017 (v1)Publication
The low-frequency dynamics of a molecular glass former has been investigated by means of inelastic neutron scattering from a mostly incoherent sample as well as by computer molecular-dynamics simulation. The mode assignments have been carried out using the neutron data for the polycrystal as well as by means of the analysis of the density of...
Uploaded on: December 2, 2022 -
April 19, 2017 (v1)Publication
The experimental curves giving the temperature dependence of the thermal conductivity of glassy selenium are considered in detail. The observed behavior can be taken into account quantitatively if the densities of states for short-wavelength phonons as well as for low-energy librations arising from computer simulations are used for the...
Uploaded on: December 4, 2022 -
May 8, 2017 (v1)Publication
The dynamics of crystalline glycerol are studied by means of Raman spectroscopy and lattice dynamics calculations employing a semiflexible model to represent the low-lying molecular vibrations. The latter is validated against structural, thermodynamic, and spectroscopic data. The results serve to set an absolute frequency scale for glassy...
Uploaded on: December 4, 2022 -
May 8, 2017 (v1)Publication
The reorientational dynamics within the rotationally disordered cubic plastic phase of solid ethanol is investigated by means of the concurrent use of computer molecular dynamics and quasielastic neutron scattering. Motions involving widely different time scales are shown to take place above the calorimetric "glass transition" which is centered...
Uploaded on: December 4, 2022 -
April 19, 2017 (v1)Publication
The elastic and total (energy-integrated) structure factors for glassy selenium have been measured by means of neutron spectroscopy within the temperature range 15 KT310 K. The correlated nature of the atomic vibrations gives rise to marked features in the total (energy-integrated) inelastic structure factors defined as the difference between...
Uploaded on: March 27, 2023 -
April 19, 2017 (v1)Publication
The microscopic low-frequency dynamics of glassy selenium is investigated by means of the concurrent use of neutron inelastic scattering and computer simulations. A separation of the dynamic response in terms of intra- and interchain processes is achieved from the analysis of the simulation results. The S(Q,E) dynamic structure factors are...
Uploaded on: December 4, 2022