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  5. VOL 39, NO 1 (2017)
  6. pp. 113-125

MODELLING OF PHASE TRANSITIONS IN CALCIUM–STRONTIUM SUPERSTRUCTURES AT LOW PRESSURES

V.V. Pozhivatenko

Èlektron. model. 2017, 39(1):113-125
https://doi.org/10.15407/emodel.39.01.113

ABSTRACT

First-principal calculations of structural phase transitions essentially underestimate the values of pressure of phase transitions in alkaline-earth metals. Using fitting parameters which are estimated in calculations for calcium and strontium the author has conducted numerical calculations of parameters of phase transitions in superstructures Ca1-xSrx consistent with face-centered cubic—body-centered cubic (FCC — BCC) transition at low pressure, modeled by the supercells containing up to sixteen atoms. Dependence of thermodynamic properties of Ca1-xSrx on concentration of strontium and parameter of smearing has been studied.

KEYWORDS

structural phase transitions, density functional theory, smearing technique for the states about Fermi level.

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