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Item _atom_site.U_iso_or_equiv

Description


              Isotropic atomic displacement parameter, or equivalent isotropic
               atomic  displacement parameter, U~equiv~, calculated from
               anisotropic atomic displacement  parameters.

               U~equiv~ = (1/3) sum~i~[sum~j~(U~ij~ A~i~ A~j~ a*~i~ a*~j~)]

               A  = the real space cell lengths
               a* = the reciprocal space cell lengths

               Ref: Fischer, R. X. & Tillmanns, E. (1988). Acta Cryst. C44,
                    775-776.

Mandatory Code

no

Data Type Code

float

Units

angstroms_squared

Enumeration Range

Minimum Value	Maximum Value
10.0	10.0
0.0	10.0
0.0	0.0

Alias Names

Alias Name	Dictionary	Version
_atom_site_U_iso_or_equiv	cif_core.dic	2.0.1

Related Items

Related Item	Related Function
_atom_site.U_iso_or_equiv_esd	associated_esd
_atom_site.B_iso_or_equiv	conversion_constant

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Resource Collaboratory for Structural Bioinformatics
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help@rcsb.rutgers.edu