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Macromolecular dictionary (mmCIF) version 2.0.09

_atom_site.B_equiv_geom_mean

Name:
'_atom_site.B_equiv_geom_mean'

Definition:

   Equivalent isotropic atomic displacement parameter, B~eq~,
   in angstroms squared, calculated as the geometric mean of
   the anisotropic atomic displacement parameters.

   B~eq~ = (B~i~ B~j~ B~k~)^1/3^

   B~n~ = the principal components of the orthogonalized B^ij^

   The IUCr Commission on Nomenclature recommends against the use
   of B for reporting atomic displacement parameters. U, being
   directly proportional to B, is preferred.

Type: float

Type conditions: esd

Mandatory item: no

Alias:
_atom_site_B_equiv_geom_mean (cif_core.dic version 2.0.1)
The permitted range is [0.0, infinity)

Related items: _atom_site.B_equiv_geom_mean_esd (associated_esd)
_atom_site.U_equiv_geom_mean (conversion_constant)

Category: atom_site