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Title: Acoustic and Thermal Vibrational Behavior of Rare Earth Glasses

Abstract

The ultrasonic wave velocity and the thermal expansion of the rare earth glasses have been measured as functions of temperature and pressure to test predictions of the soft potential model for the acoustic and thermal properties. The longitudinal ultrasonic wave velocities increase under pressure. The hydrostatic pressure derivative of the bulk modulus is positive: these glasses show a normal elastic response as compressed. However, the pressure derivative of the shear modulus is negative and small, indicating weak softening of shear modes under pressure. The results found are used to determine the Gruneisen parameters. This is to obtain the acoustic mode contribution to thermal expansion. After subtraction of the relaxation and anharmonic contributions, the temperature dependence of the shear wave ultrasound velocity follows a linear law as predicted by the Soft Potential Model.

Authors:
 [1];  [2];  [3];  [4]
  1. Department of Physical Sciences, Faculty of Science and Technology, University College of Science and Technology Malaysia (KUSTEM), 21030 Kuala Terengganu, Terengganu (Malaysia)
  2. Department of Chemistry Sciences, Faculty of Science and Technology, University College of Science and Technology Malaysia (KUSTEM), 21030 Kuala Terengganu, Terengganu (Malaysia)
  3. (Indonesia)
  4. Faculty of Science, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor (Malaysia)
Publication Date:
OSTI Identifier:
21061698
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 909; Journal Issue: 1; Conference: ICSSST 2006: 2. international conference on solid state science and technology 2006, Kuala Terengganu (Malaysia), 4-6 Sep 2006; Other Information: DOI: 10.1063/1.2739842; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; GRUENEISEN CONSTANT; PHOSPHATE GLASS; PRESSURE DEPENDENCE; RARE EARTH COMPOUNDS; RELAXATION; SHEAR; TEMPERATURE DEPENDENCE; THERMAL EXPANSION; THERMODYNAMIC PROPERTIES; ULTRASONIC WAVES; VELOCITY

Citation Formats

Senin, H. B., Kancono, W., Department of Chemical Education, The University of Bengkulu, Bengkulu 38171A, and Sidek, H. A. A.. Acoustic and Thermal Vibrational Behavior of Rare Earth Glasses. United States: N. p., 2007. Web. doi:10.1063/1.2739842.
Senin, H. B., Kancono, W., Department of Chemical Education, The University of Bengkulu, Bengkulu 38171A, & Sidek, H. A. A.. Acoustic and Thermal Vibrational Behavior of Rare Earth Glasses. United States. doi:10.1063/1.2739842.
Senin, H. B., Kancono, W., Department of Chemical Education, The University of Bengkulu, Bengkulu 38171A, and Sidek, H. A. A.. Wed . "Acoustic and Thermal Vibrational Behavior of Rare Earth Glasses". United States. doi:10.1063/1.2739842.
@article{osti_21061698,
title = {Acoustic and Thermal Vibrational Behavior of Rare Earth Glasses},
author = {Senin, H. B. and Kancono, W. and Department of Chemical Education, The University of Bengkulu, Bengkulu 38171A and Sidek, H. A. A.},
abstractNote = {The ultrasonic wave velocity and the thermal expansion of the rare earth glasses have been measured as functions of temperature and pressure to test predictions of the soft potential model for the acoustic and thermal properties. The longitudinal ultrasonic wave velocities increase under pressure. The hydrostatic pressure derivative of the bulk modulus is positive: these glasses show a normal elastic response as compressed. However, the pressure derivative of the shear modulus is negative and small, indicating weak softening of shear modes under pressure. The results found are used to determine the Gruneisen parameters. This is to obtain the acoustic mode contribution to thermal expansion. After subtraction of the relaxation and anharmonic contributions, the temperature dependence of the shear wave ultrasound velocity follows a linear law as predicted by the Soft Potential Model.},
doi = {10.1063/1.2739842},
journal = {AIP Conference Proceedings},
number = 1,
volume = 909,
place = {United States},
year = {Wed May 09 00:00:00 EDT 2007},
month = {Wed May 09 00:00:00 EDT 2007}
}
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