Hierarchical systematics of ordered perovskites: a group-theoretical analysis
نویسندگان
چکیده
منابع مشابه
Octahedral tilting in cation-ordered perovskites--a group-theoretical analysis.
Group-theoretical methods are used to enumerate the structures of ordered perovskites, in which 1:2 and 1:3 ordering of B and B' cations is considered in combination with the ubiquitous BX6 (or B'X6) octahedral tilting. The cation ordering on the B-cation site is described by irreducible representations of the Pm3 m space group of the cubic aristotype: Lambda1 (k = 1/3,1/3,1/3) for the cation o...
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Group-theoretical methods are used to analyze perovskite structures where both ferroelectric cation displacements and simple tilting of octahedral units are present. This results in a list of 40 different structures, each with a unique space-group symmetry. The list is compared with that of Aleksandrov & Bartolomé [Phase Transit. (2001), 74, 255-335] and a number of differences are found. The g...
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Applications of computer-based group-theoretical methods to perovskite crystallography are reviewed. Such methods furnish a systematic account of the effects on the high-symmetry parent structure of diverse distortions. New results are presented for elpasolites (ordered double perovskites) when both ferroelectric cation displacement and simple octahedral tilting are allowed. Group-theoretical r...
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ژورنال
عنوان ژورنال: Acta Crystallographica Section A Foundations and Advances
سال: 2017
ISSN: 2053-2733
DOI: 10.1107/s2053273317085874