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Title: Lattice dynamics of AIH{sub 3} and AID{sub 3} examined by inelastic neutron scattering.

Abstract

Inelastic neutron scattering (INS) spectra of trigonal {alpha}-AlH{sub 3} and {alpha}-AlD{sub 3} have been measured in a wide range (5-150 meV) of energy transfers with a much better statistical accuracy than previously using the inverted-geometry NERA-PR spectrometer at JINR, Dubna. The studied energy interval covers the range of low-frequency lattice vibrations and a broad band of optical H vibrations. By using a direct-geometry HRMECS spectrometer at ANL, Argonne, the AlH{sub 3} hydride was also examined by INS at energy transfers up to 315 meV in the regime of small momentum transfers. This significantly enhanced the contribution from the one-phonon neutron scattering and allowed an observation and accurate examination of one more, high-energy band of optical H vibrations predicted theoretically [C. Wolverton et al., Phys. Rev. B 69, 144109 (2004)]. Combining the obtained experimental data, the entire spectrum of phonon density of states was reconstructed for both {alpha}-AlH{sub 3} and {alpha}-AlD{sub 3}.

Authors:
; ; ; ; ; ; ;
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org.:
USDOE Office of Science (SC); RAS; INTAS
OSTI Identifier:
952199
Report Number(s):
ANL/IPNS/JA-59165
Journal ID: ISSN 1098-0121; TRN: US0902403
DOE Contract Number:
DE-AC02-06CH11357
Resource Type:
Journal Article
Resource Relation:
Journal Name: Phys. Rev. B; Journal Volume: 76; Journal Issue: 2007
Country of Publication:
United States
Language:
ENGLISH
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; ACCURACY; ANL; DUBNA; ENERGY TRANSFER; HYDRIDES; LATTICE VIBRATIONS; MOMENTUM TRANSFER; NEUTRONS; PHONONS; SCATTERING; SPECTRA; SPECTROMETERS

Citation Formats

Kolesnikov, A. I., Antonov, V. E., Markushkin, Y. E., Natkaniec, I., Sakharov, M. K., Inst. of Solid State Phys., Bochvar All-Russian Scientific Research Inst., and Frank Lab. of Neutron Physics. Lattice dynamics of AIH{sub 3} and AID{sub 3} examined by inelastic neutron scattering.. United States: N. p., 2007. Web. doi:10.1103/PhysRevB.76.064302.
Kolesnikov, A. I., Antonov, V. E., Markushkin, Y. E., Natkaniec, I., Sakharov, M. K., Inst. of Solid State Phys., Bochvar All-Russian Scientific Research Inst., & Frank Lab. of Neutron Physics. Lattice dynamics of AIH{sub 3} and AID{sub 3} examined by inelastic neutron scattering.. United States. doi:10.1103/PhysRevB.76.064302.
Kolesnikov, A. I., Antonov, V. E., Markushkin, Y. E., Natkaniec, I., Sakharov, M. K., Inst. of Solid State Phys., Bochvar All-Russian Scientific Research Inst., and Frank Lab. of Neutron Physics. Mon . "Lattice dynamics of AIH{sub 3} and AID{sub 3} examined by inelastic neutron scattering.". United States. doi:10.1103/PhysRevB.76.064302.
@article{osti_952199,
title = {Lattice dynamics of AIH{sub 3} and AID{sub 3} examined by inelastic neutron scattering.},
author = {Kolesnikov, A. I. and Antonov, V. E. and Markushkin, Y. E. and Natkaniec, I. and Sakharov, M. K. and Inst. of Solid State Phys. and Bochvar All-Russian Scientific Research Inst. and Frank Lab. of Neutron Physics},
abstractNote = {Inelastic neutron scattering (INS) spectra of trigonal {alpha}-AlH{sub 3} and {alpha}-AlD{sub 3} have been measured in a wide range (5-150 meV) of energy transfers with a much better statistical accuracy than previously using the inverted-geometry NERA-PR spectrometer at JINR, Dubna. The studied energy interval covers the range of low-frequency lattice vibrations and a broad band of optical H vibrations. By using a direct-geometry HRMECS spectrometer at ANL, Argonne, the AlH{sub 3} hydride was also examined by INS at energy transfers up to 315 meV in the regime of small momentum transfers. This significantly enhanced the contribution from the one-phonon neutron scattering and allowed an observation and accurate examination of one more, high-energy band of optical H vibrations predicted theoretically [C. Wolverton et al., Phys. Rev. B 69, 144109 (2004)]. Combining the obtained experimental data, the entire spectrum of phonon density of states was reconstructed for both {alpha}-AlH{sub 3} and {alpha}-AlD{sub 3}.},
doi = {10.1103/PhysRevB.76.064302},
journal = {Phys. Rev. B},
number = 2007,
volume = 76,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
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  • This paper reports detailed lattice dynamical studies involving experimental inelastic neutron-scattering measurements and theoretical shell model calculations of the vibrational and thermodynamic properties of the garnet mineral almandine Fe{sub 3}Al{sub 2}Si{sub 3}O{sub 12}. Inelastic neutron-scattering studies using the time-of-flight technique provide the measurement of the phonon density of states (DOS) of almandine, which have been interpreted based on the model calculations. The calculated DOS is in good agreement with the inelastic neutron-scattering data and has been used to compute various macroscopic properties like the specific heat, thermal expansion, equation of state, and mean-square atomic displacements. (c) 2000 The American Physicalmore » Society.« less
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