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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.
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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.
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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.
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@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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Journal Article:
DOI:  10.1103/PhysRevB.76.064302
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