The use of redundant coordinate bases in the construction of molecular mechanics force fields is discussed. It is shown that the intrinsic indeterminacy in a force field in redundant coordinates in general stems from the squares of the fist-order redundancy relations. The necessity to use constraint
Chiral force constants: Recommendations for the presentation of internal coordinate force constants
✍ Scribed by P.L. Polavarapu
- Publisher
- John Wiley and Sons
- Year
- 1993
- Tongue
- English
- Weight
- 166 KB
- Volume
- 14
- Category
- Article
- ISSN
- 0192-8651
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✦ Synopsis
Abstract
Some force constants associated with the internal coordinates that sense handedness or chirality can have opposite signs in the enantiomers of chiral molecules. Examples of such force constants include interaction force constants between a torsional and stretching or bending internal coordinates. The sign reversal for these force constants in the enantiomers of chiral molecules or in opposite‐handed molecular segments is best recognized by labeling them as chiral force constants. Recognition of chiral force constants suggests that certain guidelines are to be followed in the presentation of internal coordinate force constants. © 1993 by John Wiley & Sons, Inc. © John Wiley & Sons, Inc.
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