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Ab initio study of ascorbic acid conformations

✍ Scribed by Mohammad A. Al-Laham; G. A. Petersson; Paul Haake

Publisher: John Wiley and Sons
Year: 1991
Tongue: English
Weight: 569 KB
Volume: 12
Category: Article
ISSN: 0192-8651
DOI: 10.1002/jcc.540120112

No coin nor oath required. For personal study only.

✦ Synopsis

The STOSG optimized structures of nine different staggered conformers of ascorbic acid are presented. The largest energy difference between the nine local minima is 5.1 kcal/mol. Comparison of the relative energies of the fully optimized structures of ascorbic acid conformers with those of nonoptimized conformers shows that full optimization is essential to obtain meaningful results. However, optimization of the ring structure is almost independent of optimization of the side-chain structure. One of the STO-3G optimized gas phase conformers is very close to the X-ray structure of the crystal.

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