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Plane Restraints

It is possibile to apply restraints to an individual atom based on its
distance from a plane defined by the normal vector and the
atom's reference coordinate (atom properties refx, refy, refz).
An atom for which plane restraints are defined experiences restraints
only in the direction of .
Plane restraints
are defined as
where the sum extends over all atoms with negative individual weights . The symbols in Eq. 7.2 correspond to those in Eq. 7.1. By default, plane restraints are turned off. To enable plane restraints, a nonzero normal vector has to be specified using the restraints harmonic statement and assigning a negative weight for the atom property HARM. Note that plane restraints are computed only for atoms with ; otherwise point restraints (see Section 7.1.1) are applied, even if a nonzero normal vector is defined. This permits the simultaneous use of point and plane restraints, however, for disjunct sets of atoms. If , plane restraints are disabled.

*Xplor-NIH 2024-09-13*