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Reducing to Type-based Parameters
The reduce statement allows one to reduce the current
parameters (atom-based as well as type-based) to type-based
parameters using the CHEMical
atom properties (Section 4.5). Each type-based
equilibrium constant is obtained as an
average of all instances
of that type of interaction (bond, bond angle, dihedral angle,
or improper angle) in the molecular structure. The energy constants
can be obtained as a simple average or
from the same statistical analysis (Eq. 3.1) as
that used for the
learn statement. The latter option is useful only when several
instances of the same type-based interaction occur in the molecular
structure. If there is only one instance or the variance is zero, the
“reduced" energy constant is set to 999999. The periodicities (
)
of dihedral and improper angles have to be consistent for all
instances of atom-based parameters; otherwise a
warning message will occur. The “reduced" periodicities
are taken directly from the atom-based parameters.
The reduce statement affects parameters only for those interaction terms
that are turned on by the flags statement (Section
4.5).
Subsections
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