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From: "ch" <chenzhz -8 at 8- sohu.com>
To: <chemistry $#at#$ ccl.net>
Subject: OPLSAA set for carbohydrate
Date: Wed, 5 Jun 2002 10:20:15 +0800
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Dear CCLer:

I am assigning atom types to cyclodextrin. I do not make sure which types are suitable to C5-C6-O-H and C4-C5-C6-O.

The OPLSAA literature (J Comp Chem 1997, 18, 1955-1970) listed torsional parameters for carbohydrates in Table 5, and said "the torsional parameters describing the C-C-O-H torsion of simple alcohols do not optimally describe the energetics of carbohydrates, so anew set was determined...." Does this mean that the torsional parameters describing the C-C-O-H and C-C-C-O torsion of simple alcohols do not optimally describe C5-C6-O-H and C4-C5-C6-O? 

And is there torsional parameters available for C-C-C-O in alcohols?

thank you very much for any advices.

Chen