Transport properties of lithium hydride from quantum molecular dynamics and orbital-free molecular dynamics

doi:https://doi.org/10.1103/PHYSREVB.80.024305

Title: Transport properties of lithium hydride from quantum molecular dynamics and orbital-free molecular dynamics

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Abstract

We have performed a systematic study of lithium hydride in the warm-dense-matter regime for a density range from one to four times ambient solid and for temperatures from 2 to 6 eV using both finite-temperature density-functional theory quantum molecular dynamics (QMD) and orbital-free molecular dynamics (OFMD) with a focus on dynamical properties such as diffusion and viscosity. The validity of various mixing rules, especially those utilizing pressure, were checked for composite properties determined from QMD/OFMD simulations of the pure species against calculations on the fully interacting mixture. These rules produce pressures within about 10% of the full-mixture values but mutual-diffusion coefficients as different as 50%. We found very good agreement overall between the QMD, employing a three-electron pseudopotential, and the OFMD in the local-density approximation, especially at the higher temperatures and densities.

Authors:

Horner, D A; Kress, J D; Collins, L A ^[1]; Lambert, F ^[2]

Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)
CEA, DAM, DIF, F-91297 Arpajon (France)

Publication Date:: 2009-07-01

OSTI Identifier:: 21294219

Resource Type:: Journal Article

Journal Name:: Physical Review. B, Condensed Matter and Materials Physics

Additional Journal Information:: Journal Volume: 80; Journal Issue: 2; Other Information: DOI: 10.1103/PhysRevB.80.024305; (c) 2009 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 1098-0121

Country of Publication:: United States

Language:: English

Subject:: 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; APPROXIMATIONS; DENSITY; DENSITY FUNCTIONAL METHOD; DIFFUSION; ELECTRONS; LITHIUM HYDRIDES; MIXING; MIXTURES; MOLECULAR DYNAMICS METHOD; SIMULATION; SOLIDS; VISCOSITY

Citation Formats


                    Horner, D A, Kress, J D, Collins, L A, and Lambert, F. Transport properties of lithium hydride from quantum molecular dynamics and orbital-free molecular dynamics.  United States: N. p., 2009. 
        Web.  doi:10.1103/PHYSREVB.80.024305.

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                    Horner, D A, Kress, J D, Collins, L A, & Lambert, F. Transport properties of lithium hydride from quantum molecular dynamics and orbital-free molecular dynamics.  United States.  https://doi.org/10.1103/PHYSREVB.80.024305

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                    Horner, D A, Kress, J D, Collins, L A, and Lambert, F. Wed .  
        "Transport properties of lithium hydride from quantum molecular dynamics and orbital-free molecular dynamics".  United States.  https://doi.org/10.1103/PHYSREVB.80.024305.

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@article{osti_21294219,

  title        = {Transport properties of lithium hydride from quantum molecular dynamics and orbital-free molecular dynamics},

  author       = {Horner, D A and Kress, J D and Collins, L A and Lambert, F},

  abstractNote = {We have performed a systematic study of lithium hydride in the warm-dense-matter regime for a density range from one to four times ambient solid and for temperatures from 2 to 6 eV using both finite-temperature density-functional theory quantum molecular dynamics (QMD) and orbital-free molecular dynamics (OFMD) with a focus on dynamical properties such as diffusion and viscosity. The validity of various mixing rules, especially those utilizing pressure, were checked for composite properties determined from QMD/OFMD simulations of the pure species against calculations on the fully interacting mixture. These rules produce pressures within about 10% of the full-mixture values but mutual-diffusion coefficients as different as 50%. We found very good agreement overall between the QMD, employing a three-electron pseudopotential, and the OFMD in the local-density approximation, especially at the higher temperatures and densities.},

  doi          = {10.1103/PHYSREVB.80.024305},

  url          = {https://www.osti.gov/biblio/21294219},
  journal      = {Physical Review. B, Condensed Matter and Materials Physics},

  issn         = {1098-0121},

  number       = 2,

  volume       = 80,

  place        = {United States},

  year         = {2009},

  month        = {7}

}

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