From asmellie #at# combichem.com Thu Oct 29 16:57:02 1998

I see one problem immediately with this approach:

As you step the torsions, one might expect internal bond angles to change.
In particular, as VDW interactions rise as 1 / R^12, as two atoms get
closer during the torsion rotation, internal bond angles are likely
to open to relieve the VDW energy. Look at the example of
the central torsion of butane:

C1---C--(T)--C---C2

If T = 180, C1 and C2 are maximally distant and VDW energy in minimized

If T = 0, C1 and C2 are closest and one or more of the internal C-C-C bond
angles opens to relieve the strain.

Hope this helps,

--andrew



Dr. Andrew Smellie,
CombiChem Inc.
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Palo Alto, CA 94303
Phone: (650)-842-0560
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email: asmellie ^at^ combichem.com



Answer 5: