Difference between revisions of "Aristotype"
From Online Dictionary of Crystallography
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| − | < | + | <font color="blue">Aristotype</font> (''Fr''). <font color="red">Aristotyp</font> (''Ge''). <font color="black">Aristotipo</font> (''It''). <font color="purple">アリストタイプ</font> (''Ja''). <font color="green">Aristotipo</font> (''Sp''). |
| + | == Definition == | ||
| − | + | An aristotype is a high-symmetry structure type that can be viewed as an idealized version of a lower-symmetry structure. It was introduced by Helen Megaw in relation to perovskites, where it is still mostly used. The cubic perovskite structure (which is adopted at most by half a dozen compounds) is regarded as the aristotype for the vast array of other lower-symmetry perovskites. The lower-symmetry structure is called '''hettotype'''. | |
| − | + | After Buerger, aristotypes are also known as '''basic structures''' and hettotypes as '''derivative structures'''. | |
Originally, an aristotype is a printing-out process using paper coated with silver chloride in gelatin; now, any such process using silver salts in either collodion or gelatin; also, a print so made. | Originally, an aristotype is a printing-out process using paper coated with silver chloride in gelatin; now, any such process using silver salts in either collodion or gelatin; also, a print so made. | ||
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== References == | == References == | ||
| − | Megaw H. (1973). ''Crystal Structures'', London: W.B. Saunders, | + | *Buerger, M. J. (1947). ''J. Chem. Phys.'' '''15''', 1-16. ''Derivative Crystal Structures''. |
| − | + | *Megaw, H. (1973). ''Crystal Structures'', London: W. B. Saunders, pp. 216, 282. | |
| − | |||
[[Category:Fundamental crystallography]] | [[Category:Fundamental crystallography]] | ||
Latest revision as of 18:02, 8 November 2017
Aristotype (Fr). Aristotyp (Ge). Aristotipo (It). アリストタイプ (Ja). Aristotipo (Sp).
Definition
An aristotype is a high-symmetry structure type that can be viewed as an idealized version of a lower-symmetry structure. It was introduced by Helen Megaw in relation to perovskites, where it is still mostly used. The cubic perovskite structure (which is adopted at most by half a dozen compounds) is regarded as the aristotype for the vast array of other lower-symmetry perovskites. The lower-symmetry structure is called hettotype.
After Buerger, aristotypes are also known as basic structures and hettotypes as derivative structures.
Originally, an aristotype is a printing-out process using paper coated with silver chloride in gelatin; now, any such process using silver salts in either collodion or gelatin; also, a print so made.
References
- Buerger, M. J. (1947). J. Chem. Phys. 15, 1-16. Derivative Crystal Structures.
- Megaw, H. (1973). Crystal Structures, London: W. B. Saunders, pp. 216, 282.