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Difference between revisions of "Isomorphous crystals"

From Online Dictionary of Crystallography

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<Font color="blue">Cristaux isomorphes </Font>(''Fr''). <Font color="green"> Cristales isomorfos</Font> (''Sp'').
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<Font color="blue">Cristaux isomorphes </Font>(''Fr''). <Font color="red"> Isomorphe Kristalle </Font> (''Ge''). <Font color="green"> Cristales isomorfos</Font> (''Sp'').
  
  
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Two crystals are said to be isomorphous if (''a'') both have the same space group and unit-cell dimensions and (''b'') the types and the positions of atoms in both are the same except for a replacement of one or more atoms in one structure with different types of atoms in the other ([[isomorphous replacement]]), such as heavy atoms, or the presence of one or more additional atoms in one of them (''isomorphous addition''). Isomorphous crystals can form ''solid solutions''.
 
Two crystals are said to be isomorphous if (''a'') both have the same space group and unit-cell dimensions and (''b'') the types and the positions of atoms in both are the same except for a replacement of one or more atoms in one structure with different types of atoms in the other ([[isomorphous replacement]]), such as heavy atoms, or the presence of one or more additional atoms in one of them (''isomorphous addition''). Isomorphous crystals can form ''solid solutions''.
  
== History == The notion of isomorphism was discovered by Mitscherlich who found that the crystal forms of salts such as the hydrated potassium copper and iron sulfates or the hydrated potassium phosphates and arsenates were identical (1819, 1820).
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== History == The notion of isomorphism was discovered by Mitscherlich who found that the crystal forms of salts such as the hydrated potassium phosphates and arsenates or the hydrated potassium copper and iron sulfates were identical (1819, 1820).
 
 
  
 
== See also ==
 
== See also ==
  
 
Section 2.4 of ''International Tables of Crystallography, Volume B''
 
Section 2.4 of ''International Tables of Crystallography, Volume B''

Revision as of 07:13, 12 February 2006

Cristaux isomorphes (Fr). Isomorphe Kristalle (Ge). Cristales isomorfos (Sp).


Definition

Two crystals are said to be isomorphous if (a) both have the same space group and unit-cell dimensions and (b) the types and the positions of atoms in both are the same except for a replacement of one or more atoms in one structure with different types of atoms in the other (isomorphous replacement), such as heavy atoms, or the presence of one or more additional atoms in one of them (isomorphous addition). Isomorphous crystals can form solid solutions.

== History == The notion of isomorphism was discovered by Mitscherlich who found that the crystal forms of salts such as the hydrated potassium phosphates and arsenates or the hydrated potassium copper and iron sulfates were identical (1819, 1820).

See also

Section 2.4 of International Tables of Crystallography, Volume B