Aristotype

From Online Dictionary of Crystallography

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An arisotype in crystallography is a high-symmetry structure type that can be viewed as an idealized version of a lower symmetry structure.  I believe Helen Megaw introduced the term 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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<Font color="blue">Aristotype</Font> (''Fr'').
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Orig., 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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== 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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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.

Revision as of 05:39, 21 October 2006

Aristotype (Fr).


Definition

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.

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.