Macromolecular dictionary (mmCIF) version 2.0.09
_atom_site.U_iso_or_equiv
Name:'_atom_site.U_iso_or_equiv'
Definition:
Isotropic atomic displacement parameter, or equivalent isotropic atomic displacement parameter, U~eq~, calculated from anisotropic atomic displacement parameters. U~eq~ = (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.
Type: float
Type conditions: esd
Mandatory item: no
Alias:_atom_site_U_iso_or_equiv (cif_core.dic version 2.0.1)
The permitted range is [0.0, 10.0]
Related items: _atom_site.U_iso_or_equiv_esd (associated_esd)
_atom_site.B_iso_or_equiv (conversion_constant)
Category: atom_site