Symmetry and space groups: Difference between revisions

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== Reflection conditions ==
== Reflection conditions ==


These are explained and listed in Section 2.2.13 of International Tables of Crystallography, Volume A . If this is not on your desk, check out the IUCr wiki:
These are explained and listed in Section 2.2.13 of International Tables of Crystallography, Volume A . If this is not on your desk, check out the [http://reference.iucr.org/dictionary/Main_Page IUCr wiki]:


[[iucr:Reflection_conditions|Reflection_conditions]] which explains the topic, and links to lists of the general absences in article [[iucr:Integral_reflection_conditions|Integral_reflection_conditions]], and the absences along the screw axes in [[iucr:Serial_reflection_conditions|Serial_reflection_conditions]]
[[iucr:Reflection_conditions|Reflection_conditions]] which explains the topic, and links to lists of the general absences in article [[iucr:Integral_reflection_conditions|integral reflection conditions]], and the absences along the screw axes in [[iucr:Serial_reflection_conditions|serial reflection conditions]].

Latest revision as of 20:33, 11 May 2008

Space group operators can be found here: http://www.embl-hamburg.de/~pinotsis/spacegroup.html

The crystallographic toolbox is at [1]. Its predecessor, SgInfo, is here.


Facts about space groups[edit | edit source]

There are 230 space groups, 65 of which accessible to proteins.

Empirically, P212121 is the space group which occurs most often (23%) in the PDB; second place is P21 with 14.4%, then comes C2 (9.0%) ( [2]).

Reflection conditions[edit | edit source]

These are explained and listed in Section 2.2.13 of International Tables of Crystallography, Volume A . If this is not on your desk, check out the IUCr wiki:

Reflection_conditions which explains the topic, and links to lists of the general absences in article integral reflection conditions, and the absences along the screw axes in serial reflection conditions.