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Index

Macromolecular dictionary (mmCIF) version 2.0.09

Category VALENCE_PARAM

Name:
'valence_param'

Description:

   Data items in the VALENCE_PARAM category define the
   parameters used for calculating bond valences from bond
   lengths.  In addition to the parameters, a pointer
   is given to the reference (in VALENCE_REF) from which
   the bond-valence parameters were taken.

Example:

Example 1 - a bond-valence parameter list with accompanying references. 
 
    loop_
    _valence_param.atom_1
    _valence_param.atom_1_valence
    _valence_param.atom_2
    _valence_param.atom_2_valence
    _valence_param.Ro
    _valence_param.B
    _valence_param.ref_id
    _valence_param.details
      Cu 2 O -2 1.679 0.37 a .
      Cu 2 O -2 1.649 0.37 j .
      Cu 2 N -3 1.64  0.37 m '2-coordinate N'
      Cu 2 N -3 1.76  0.37 m '3-coordinate N'
    loop_
    _valence_ref.id
    _valence_ref.reference
      a  'Brown & Altermatt (1985), Acta Cryst. B41, 244-247'
      j  'Liu & Thorp (1993), Inorg. Chem. 32, 4102-4205'
      m  'See, Krause & Strub (1998), Inorg. Chem. 37, 5369-5375'


Category keys:
    _valence_param.atom_1
    _valence_param.atom_1_valence
    _valence_param.atom_2
    _valence_param.atom_2_valence

Mandatory category: no


International Tables for Crystallography

Volume G: Definition and exchange of crystallographic data

First online edition (2006)

Edited by S. R. Hall and B. McMahon

An essential guide and reference to CIF for programmers, data managers handling crystal-structure information and practising crystallographers.