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Core CIF Dictionary version 2.3




Category: geom_torsion

Data type: numb (with optional s.u. in parentheses)

Must appear in a looped list containing '_geom_torsion_atom_site_label_'

Units: deg ( degrees)


   The torsion angle in degrees bounded by the four atom sites
   identified by the _geom_torsion_atom_site_label_ codes. These
   must match labels specified as _atom_site_label in the atom list.
   The torsion angle definition should be that of Klyne and Prelog.

   Ref: Klyne, W. & Prelog, V. (1960). Experientia, 16, 521-523.

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