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Usually used for non-bonded distances:
![\begin{displaymath}
c = \left[(\frac{A}{f})^{12} - (\frac{B}{f})^6 \right] s(f,f_1,f_2)
\end{displaymath}](img356.png) |
(7.62) |
The parameters
and
of the switching function can be
different from those in Eq. 5.59. The parameters
and
are obtained from the CHARMM parameter file (NONBOND section)
where they are given as
and
such that
in kcal/mole
for
in angstroms and
; the minimum of
is
at
, and its zero is at
. The total Lennard-Jones energy should be evaluated over all
pairs of atoms that are not in the same bonds or bond angles. The
parameters
and
for 1-4 pairs in dihedral angles can be
different from those for the other pairs; they are obtained from the
second set of
and
in the CHARMM parameter file, if it
exists. 1-4 energy corresponds to the LJ14 MODELLER term; the
remaining longer-range contribution corresponds to the LJ term.
The first derivatives are:
Next: Spline restraint
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Bozidar BJ Jerkovic
2001-12-21