The correct symmetry of the six-fold twin in β-Ca11B2Si4O22
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Massimo Nespolo
Abstract
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.
Acknowledgements
Critical remarks by two anonymous reviewers are gratefully acknowledged.
References
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©2018 Walter de Gruyter GmbH, Berlin/Boston
Articles in the same Issue
- Frontmatter
- Graphical Synopsis
- Recent advances in the chemistry of uranium halides in anhydrous ammonia
- The correct symmetry of the six-fold twin in β-Ca11B2Si4O22
- The allotwinning of KCa3Te5O12Cl3: an OD interpretation
- Zippeite from Cap Garonne, France: an example of reticular twinning
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Articles in the same Issue
- Frontmatter
- Graphical Synopsis
- Recent advances in the chemistry of uranium halides in anhydrous ammonia
- The correct symmetry of the six-fold twin in β-Ca11B2Si4O22
- The allotwinning of KCa3Te5O12Cl3: an OD interpretation
- Zippeite from Cap Garonne, France: an example of reticular twinning
- Structural studies on copper and nitrogen doped nanosized anatase
- Low-dimensional compounds containing cyanido groups. Part XXXIV. Structure, spectral and magnetic properties of the first complex with pyridylbenzimidazole and nonlinear pseudohalide anion
