کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1811874 1025603 2011 7 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
High pressure lattice dynamics, dielectric and thermodynamic properties of SrO
موضوعات مرتبط
مهندسی و علوم پایه فیزیک و نجوم فیزیک ماده چگال
پیش نمایش صفحه اول مقاله
High pressure lattice dynamics, dielectric and thermodynamic properties of SrO
چکیده انگلیسی

Using density functional theory and density functional perturbation theory we have studied the effects of hydrostatic pressure on lattice dynamics, dielectric and thermodynamic properties of the rocksalt (NaCl) and CsCl phases of SrO. The stability of the NiAs type structure, experimentally confirmed to be stable in BaO, is also investigated. Studying the lattice dynamics of the NaCl and CsCl phases at various pressures, in the range of the phase stability, we have found the lattice dynamical instabilities which govern the phase transitions between NaCl and CsCl phases with increasing and decreasing pressure. By monitoring the behaviour of the found soft modes, we have calculated the transition pressures upon compression and decompression of SrO crystal. Lattice dynamics calculations reveal that the rocksalt and CsCl structures are unstable with respect to the soft transversal acoustic modes at single points of the Brillouin zone, which points to the fact that the transitions are of displacive type. Responses to electric fields and thermodynamic properties at high pressures are also given and discussed. All our results are in a good agreement with experimental data where applicable.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Physica B: Condensed Matter - Volume 406, Issue 18, 15 September 2011, Pages 3410–3416
نویسندگان
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