Index

Core dictionary version 3.3.0

_atom_site_aniso.U_12

Definition:

   
     These are the standard anisotropic atomic displacement components in
     angstroms squared which appear in the structure-factor term

    T = exp{ -2π^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

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

     The IUCr Commission on Nomenclature recommends the use of U for reporting
     atomic displacement parameters.

     Note that U^ij^ = β^ij^/(2 π^2^ a*~i~ a*~j~) = B^ij^/(8 π^2^).

     Ref: Trueblood, K. N. et al. (1996). Acta Cryst. A52, 770-781.

Type: Real

Units: angstrom_squared

Category:
atom_site_aniso