X-PLOR provides a means to
restrain the main coordinate set ( atom properties x,y,z)
to the reference coordinate
set (atom properties refx, refy, refz). The restraints
are defined as
(7.1)
where the sum extends over all atoms, is individual weights,
is the atomic coordinates of the main set, is
the atomic coordinates of the reference set, and is an
exponent. The individual weights correspond to
the atom property HARM and can be assigned
using the vector statement
(Section 2.16); the physical dimension of HARM is
kcal mole Å. By default, is zero. The
reference coordinate set can be assigned using the
vector statement or by using the DISPosition option of
the coordinate statement. The exponent is set
by using the restraints harmonic statement.