Devonshire-Landau free energy ofBaTiO3from first principles
نویسندگان
چکیده
منابع مشابه
Fluctuations and Landau-Devonshire expansion for Barium Titanate
The experimentally observed temperature dependence of the quartic coefficients in the Landau-Devonshire expansion for BaTiO3 is naturally accounted for within a proper fluctuation model. It is explained, in particular, why one of the quartic coefficients varies with temperature above Tc while the second is constant. The tetragonal phase in BaTiO3 is argued to exist essentially due to the therma...
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ژورنال
عنوان ژورنال: Physical Review B
سال: 2001
ISSN: 0163-1829,1095-3795
DOI: 10.1103/physrevb.63.144103