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Item _atom_site_anisotrop.U[3][3]


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Description


              The [3][3] element of the standard anisotropic atomic
               displacement matrix U, which appears in the structure factor
               term as:

               T = exp{-2 pi^2^ sum~i~[sum~j~(U~ij~ h~i~ h~j~ a*~i~ a*~j~)]}

               h  = the Miller indices
               a* = the reciprocal space cell lengths

               These matrix elements may appear with atomic coordinates
               in the ATOM_SITE category, or they may appear in the separate
               ATOM_SITE_ANISOTROP category, but they may not appear in both
               places. Similarly, anisotropic displacements may appear as
               either B's or U's, but not as both.

               The unique elements of the real symmetric matrix are
               entered by row.

Category

atom_site_anisotrop

Mandatory Code

no

Data Type Code

float

Units

angstroms_squared

Alias Names

Alias Name Dictionary Version
_atom_site_aniso_U_33 cif_core.dic 2.0.1

Related Items

Related Item Related Function
_atom_site_anisotrop.U[3][3]_esd associated_esd
_atom_site.aniso_B[3][3] conversion_constant
_atom_site_anisotrop.B[3][3] conversion_constant
_atom_site.aniso_B[3][3] alternate_exclusive
_atom_site.aniso_U[3][3] alternate_exclusive
_atom_site_anisotrop.B[3][3] alternate_exclusive

Subcategories


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