Phase diagram and thermodynamic properties of solid magnesium in the quasiharmonic approximation

doi:https://doi.org/10.1103/PhysRevB.48.13253

Title: Phase diagram and thermodynamic properties of solid magnesium in the quasiharmonic approximation

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Abstract

Using a family of volume-dependent interatomic pair potentials derived from first principles, we calculate phonon properties and thermodynamic functions in the quasiharmonic approximation for the hcp and bcc phases of Mg over a wide range of volume and temperature. At atmospheric pressure, the calculated hcp phonon-dispersion curves and thermodynamic properties agree well with experiment. The pressure dependence of the Raman-active transverse-optical phonon mode also agrees well with very recent measurements. At high pressure, the temperature dependence of the hcp-bcc phase line is predicted, with values of the transition pressure ranging from 52 GPa at zero temperature to about 28 GPa at 1000 K.

Authors:

Althoff, J D; Allen, P B; Wentzcovitch, R M ^[1]; Moriarty, J A ^[2]

Department of Physics, State University of New York at Stony Brook, Stony Brook, New York 11794 (United States)
Lawrence Livermore National Laboratory, University of California, Livermore, California 94550 (United States)

Publication Date:: 1993-11-01

OSTI Identifier:: 5910279

DOE Contract Number:: AC02-76CH00016; W-7405-ENG-48

Resource Type:: Journal Article

Journal Name:: Physical Review, B: Condensed Matter; (United States)

Additional Journal Information:: Journal Volume: 48:18; Journal ID: ISSN 0163-1829

Country of Publication:: United States

Language:: English

Subject:: 36 MATERIALS SCIENCE; MAGNESIUM; PHASE DIAGRAMS; BCC LATTICES; ELECTRONIC STRUCTURE; HCP LATTICES; PHONONS; THERMODYNAMIC PROPERTIES; ALKALINE EARTH METALS; CRYSTAL LATTICES; CRYSTAL STRUCTURE; CUBIC LATTICES; DIAGRAMS; ELEMENTS; HEXAGONAL LATTICES; METALS; PHYSICAL PROPERTIES; QUASI PARTICLES; 360102* - Metals & Alloys- Structure & Phase Studies; 360104 - Metals & Alloys- Physical Properties

Citation Formats


                    Althoff, J D, Allen, P B, Wentzcovitch, R M, and Moriarty, J A. Phase diagram and thermodynamic properties of solid magnesium in the quasiharmonic approximation.  United States: N. p., 1993. 
        Web.  doi:10.1103/PhysRevB.48.13253.

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                    Althoff, J D, Allen, P B, Wentzcovitch, R M, & Moriarty, J A. Phase diagram and thermodynamic properties of solid magnesium in the quasiharmonic approximation.  United States.  https://doi.org/10.1103/PhysRevB.48.13253

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                    Althoff, J D, Allen, P B, Wentzcovitch, R M, and Moriarty, J A. Mon .  
        "Phase diagram and thermodynamic properties of solid magnesium in the quasiharmonic approximation".  United States.  https://doi.org/10.1103/PhysRevB.48.13253.

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@article{osti_5910279,

  title        = {Phase diagram and thermodynamic properties of solid magnesium in the quasiharmonic approximation},

  author       = {Althoff, J D and Allen, P B and Wentzcovitch, R M and Moriarty, J A},

  abstractNote = {Using a family of volume-dependent interatomic pair potentials derived from first principles, we calculate phonon properties and thermodynamic functions in the quasiharmonic approximation for the hcp and bcc phases of Mg over a wide range of volume and temperature. At atmospheric pressure, the calculated hcp phonon-dispersion curves and thermodynamic properties agree well with experiment. The pressure dependence of the Raman-active transverse-optical phonon mode also agrees well with very recent measurements. At high pressure, the temperature dependence of the hcp-bcc phase line is predicted, with values of the transition pressure ranging from 52 GPa at zero temperature to about 28 GPa at 1000 K.},

  doi          = {10.1103/PhysRevB.48.13253},

  url          = {https://www.osti.gov/biblio/5910279},
  journal      = {Physical Review, B: Condensed Matter; (United States)},

  issn         = {0163-1829},

  number       = ,

  volume       = 48:18,

  place        = {United States},

  year         = {1993},

  month        = {11}

}

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