Aristotype

From Online Dictionary of Crystallography

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== Definition ==
== Definition ==
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An arisotype 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 which it is where it is still mostly used, the cubic perovskite structure (which is adopted at most half a dozen compounds) is regarded as the aristotype for the vast array of other lower-symmetry perovskites.
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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.
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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== R eferences ==
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== References ==
Megaw H. (1973). ''Crystal Structures'', London: W.B. Saunders,  p. 216, 282
Megaw H. (1973). ''Crystal Structures'', London: W.B. Saunders,  p. 216, 282

Revision as of 08:35, 25 May 2007

Aristotype (Fr). Aristotipo (It).


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.

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

Megaw H. (1973). Crystal Structures, London: W.B. Saunders, p. 216, 282