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.