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Zeitschrift für Kristallographie - Crystalline Materials

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The correct symmetry of the six-fold twin in β-Ca11B2Si4O22

Massimo Nespolo
Published Online: 2018-06-16 | DOI: https://doi.org/10.1515/zkri-2018-2094


A recently reported six-fold twin in β-Ca11B2Si4O22 was interpreted as a transformation twin obtained during cooling of a hypothetical hexagonal high temperature phase. The suggested dichromatic symmetry of the twin is incorrect because (1) a six-fold twin cannot be represented by a dichromatic twin point group but by a hexachromatic group; (2) the reported dichromatic group does not exist. The correct hexachromatic twin point group is reported here.

Keywords: polychromatic symmetry; twin point groups; twinning


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About the article

Received: 2018-05-03

Accepted: 2018-05-25

Published Online: 2018-06-16

Citation Information: Zeitschrift für Kristallographie - Crystalline Materials, 20182094, ISSN (Online) 2196-7105, ISSN (Print) 2194-4946, DOI: https://doi.org/10.1515/zkri-2018-2094.

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