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International
Tables for Crystallography Volume G Definition and exchange of crystallographic data Edited by J. R. Hester and B. McMahon © International Union of Crystallography 2026 |
International Tables for Crystallography (2026). Vol. G. Early view chapter
https://doi.org/10.1107/97809553602060001011 Chapter 4.2 Core dictionary (coreCIF) |
Core dictionary version 3.3.0
_atom_site.U_equiv_geom_mean
Name:_atom_site.U_equiv_geom_mean
Alias:
_atom_site_U_equiv_geom_mean
Definition:
Equivalent isotropic atomic displacement parameter, U(equiv),
in angstroms squared, calculated as the geometric mean of
the anisotropic atomic displacement parameters.
U(equiv) = (U~i~ U~j~ U~k~)^1/3^
U~n~ = the principal components of the orthogonalized U^ij^.
Type: Real
Units: angstrom_squared
The permitted range is 0.0 → infinity
Category:
atom_site
