Difference between revisions of "Systematic absences"
From Online Dictionary of Crystallography
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| − | <Font color="blue">Absences systématiques</Font> (''Fr''). <Font color="green"> Extinciones sistemáticas </Font> (''Sp''). <Font color="black">Assenze sistematiche, estinzioni sistematiche </Font>(''It''). <Font color="purple">消滅則</Font> (''Ja'') | + | <Font color="blue">Absences systématiques</Font> (''Fr''). <Font color="green"> Extinciones sistemáticas </Font> (''Sp''). <Font color="black">Assenze sistematiche, estinzioni sistematiche </Font>(''It''). <Font color="purple">消滅則</Font> (''Ja''). |
== Definition == | == Definition == | ||
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== See also == | == See also == | ||
| − | *[[ | + | *[[Reflection conditions]] |
| − | * | + | *Chapter 1.6.4 of ''International Tables for Crystallography, Volume A'', 6th edition |
| − | [[Category:X-rays]] | + | [[Category:X-rays]] |
Revision as of 12:01, 17 May 2017
Absences systématiques (Fr). Extinciones sistemáticas (Sp). Assenze sistematiche, estinzioni sistematiche (It). 消滅則 (Ja).
Definition
One speaks of systematic absences or extinctions when the structure factor is zero, due either to the centring of the lattice or to the presence of glide or screw symmetry elements. Conversely, the conditions for a reflection to exist and not to be systematically absent, are called reflection conditions.
See also
- Reflection conditions
- Chapter 1.6.4 of International Tables for Crystallography, Volume A, 6th edition