{ minimize-rigid-statement } END is
invoked from the main level of X-PLOR.
minimize-rigid-statement :==
DROP=real
designates the expected initial drop in energy
(default: 1).
GROUp=selection
selects atoms that will be
forming a rigid group. Multiple specification of GROUps will define
multiple rigid groups. The group selections have to be
disjoint (default: one group consisting of all nonfixed atoms).
The default is overwritten as soon as a GROUp statement is issued.
NPRInt=integer
is the frequency of the energy printout (default: 1).
NSTEp=integer
is the maximum number of minimization cycles
(default: 50).
TOLErance=real
stops minimization if the norm of
the gradient of the energy function is smaller than
the specified number (default: 0.01).