Pressure dependent elastic constants of alpha and gamma cyclotrimethylene trinitramine: A quantum mechanical study

doi:10.1063/1.4891999

Title: Pressure dependent elastic constants of alpha and gamma cyclotrimethylene trinitramine: A quantum mechanical study

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Abstract

The elastic constants of the α and γ polymorphs of cyclotrimethylene trinitramine (RDX) have been computed using dispersion corrected density functional theory (DFT). The DFT results validate the values obtained in several experiments using ultrasonic and impulsive stimulated thermal scattering techniques and disagree with those obtained using Brillouin scattering which, in general, exceed the other experimental and theoretical results. Compressibility diagrams at zero pressure are presented for the ab, ac, and bc crystallographic planes, and the anisotropic linear compressibility within the ac plane of α-RDX at 0 GPa, observed using ultrasonic and impulsive stimulated thermal scattering measurements, is verified using DFT. The pressure dependence of the elastic constants of α-RDX (0–4 GPa) and γ-RDX (4–8 GPa) is also presented.

Authors:

Taylor, DeCarlos E., E-mail: decarlos.e.taylor.civ@mail.mil ^[1]

U.S. Army Research Laboratory, Aberdeen Proving Ground, Maryland 21005 (United States)

Publication Date:: Thu Aug 07 00:00:00 EDT 2014

OSTI Identifier:: 22314541

Resource Type:: Journal Article

Journal Name:: Journal of Applied Physics

Additional Journal Information:: Journal Volume: 116; Journal Issue: 5; Other Information: (c) 2014 U.S. Government; Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 0021-8979

Country of Publication:: United States

Language:: English

Subject:: 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ANISOTROPY; BRILLOUIN EFFECT; COMPRESSIBILITY; CRYSTALLOGRAPHY; DENSITY FUNCTIONAL METHOD; DIAGRAMS; PRESSURE DEPENDENCE; PRESSURE RANGE GIGA PA; QUANTUM MECHANICS

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                    Taylor, DeCarlos E., E-mail: decarlos.e.taylor.civ@mail.mil. Pressure dependent elastic constants of alpha and gamma cyclotrimethylene trinitramine: A quantum mechanical study.  United States: N. p., 2014. 
        Web.  doi:10.1063/1.4891999.

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                    Taylor, DeCarlos E., E-mail: decarlos.e.taylor.civ@mail.mil. Pressure dependent elastic constants of alpha and gamma cyclotrimethylene trinitramine: A quantum mechanical study.  United States.  https://doi.org/10.1063/1.4891999

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                    Taylor, DeCarlos E., E-mail: decarlos.e.taylor.civ@mail.mil. 2014.  
        "Pressure dependent elastic constants of alpha and gamma cyclotrimethylene trinitramine: A quantum mechanical study".  United States.  https://doi.org/10.1063/1.4891999.

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@article{osti_22314541,

  title        = {Pressure dependent elastic constants of alpha and gamma cyclotrimethylene trinitramine: A quantum mechanical study},

  author       = {Taylor, DeCarlos E., E-mail: decarlos.e.taylor.civ@mail.mil},

  abstractNote = {The elastic constants of the α and γ polymorphs of cyclotrimethylene trinitramine (RDX) have been computed using dispersion corrected density functional theory (DFT). The DFT results validate the values obtained in several experiments using ultrasonic and impulsive stimulated thermal scattering techniques and disagree with those obtained using Brillouin scattering which, in general, exceed the other experimental and theoretical results. Compressibility diagrams at zero pressure are presented for the ab, ac, and bc crystallographic planes, and the anisotropic linear compressibility within the ac plane of α-RDX at 0 GPa, observed using ultrasonic and impulsive stimulated thermal scattering measurements, is verified using DFT. The pressure dependence of the elastic constants of α-RDX (0–4 GPa) and γ-RDX (4–8 GPa) is also presented.},

  doi          = {10.1063/1.4891999},

  url          = {https://www.osti.gov/biblio/22314541},
  journal      = {Journal of Applied Physics},

  issn         = {0021-8979},

  number       = 5,

  volume       = 116,

  place        = {United States},

  year         = {Thu Aug 07 00:00:00 EDT 2014},

  month        = {Thu Aug 07 00:00:00 EDT 2014}

}

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