A multicentered approach to integrated QM/QM calculations. Applications to multiply hydrogen bonded systems
✍ Scribed by Brian W. Hopkins; Gregory S. Tschumper
- Publisher
- John Wiley and Sons
- Year
- 2003
- Tongue
- English
- Weight
- 120 KB
- Volume
- 24
- Category
- Article
- ISSN
- 0192-8651
No coin nor oath required. For personal study only.
✦ Synopsis
Abstract
A multicentered integrated QM/QM technique has been developed. By separating high‐level calculations in distinct regions of molecules, the multicentered approach supplants a single large high‐level calculation with several smaller calculations. Due to the steep polynomial scaling of traditional ab initio quantum chemical methods, this separation significantly enhances the computational efficiency of QM/QM methods. The straightforward implementation of this multicentered approach is illustrated with several large poly‐alcohols that form hydrogen bonds with water. The largest alcohol–water complex contains 81 atoms. For properly selected model systems, this multicentered approach introduces essentially no error in the dissociation energies of these complexes relative to conventional QM/QM schemes. This multicentered technique should be easily extended to other, more general integrated methods (QM/MM, ONIOM, etc). © 2003 Wiley Periodicals, Inc. J Comput Chem 24: 1563–1568, 2003