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Vibrational and thermoelastic properties of bcc iron from selected EAM potentials

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 نشر من قبل Davide Ceresoli
 تاريخ النشر 2016
  مجال البحث فيزياء
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A comprehensive, critical study of the vibrational, thermodynamic and thermoelastic properties of bcc iron is presented, using well established semi-empirical embedded-atom method potentials available in the literature. Classical molecular dynamics simulations are used to address temperature effects, where dynamical matrices are constructed as a time average of the second moment of the atomic displacements. The $C_{11}, C_{44}, C$ elastic constants are then obtained from the sound velocities along high symmetry directions in reciprocal space. Results are compared to ultrasonic measurements and highlight the limitations of the potentials considered here in describing thermoelastic properties.



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