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Twin model for orthorhombic perovskites

Bas B. Van Aken·Auke Meetsma·Thomas T. M. Palstra
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Abstract

We present a detailed single crystal x-ray diffraction study of twinned orthorhombic perovskites. The diffraction pattern can be indexed on a $2a_p$x$2a_p$x$2a_p$ lattice, but does not obey cubic symmetry relations. The data can be modelled in space group $Pnma$ with a twin based on a distribution of the $b$ axis over three perpendicular cubic axes. This model allows full structure determination in the presence of up to six twin fractions from single crystal x-ray diffraction data.

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Bas B. Van Aken, Auke Meetsma, Thomas T. M. Palstra. 2001-03-30. Twin model for orthorhombic perovskites. https://arxiv.org/abs/cond-mat/0103628

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