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Macromolecular dictionary (mmCIF) version 2.0.09

_struct_mon_nucl.P

Name:
'_struct_mon_nucl.P'

Definition:

   P is the phase angle of pseudorotation for five-membered rings.
   For ribose and deoxyribose sugars in nucleic
   acids
              (tau4 +tau1)-(tau3+tau0)
   P = ATAN (-------------------------)
               2tau2 (sin 36+sin 72)

   If tau2 is <0, then P=P+180 degree (Altona & Sundaralingam,
   1972).

   Ref: Altona, C. & Sundaralingam, M. (1972).
   J. Am. Chem. Soc. 94, 8205-8212.

Type: float

Mandatory item: no

Category: struct_mon_nucl