Skip to main content
Article thumbnail
Location of Repository

Evaluation and Optimization of a Force Field for Crystalline Forms of Mannitol and Sorbitol

By H. de Waard, A. Amani, John Kendrick, W.L.J. Hinrichs, H.W. Frijlink and Jamshed Anwar

Abstract

NoTwo force fields, the GROMOS53A5/53A6 (united atom) and the AMBER95 (all atom) parameter sets, coupled with partial atomic charges derived from quantum mechanical calculations were evaluated for their ability to reproduce the known crystalline forms of the polyols mannitol and sorbitol. The force fields were evaluated using molecular dynamics simulations at 10 K (which is akin to potential energy minimization) with the simulation cell lengths and angles free to evolve. Both force fields performed relatively poorly, not being able to simultaneously reproduce all of the crystal structures within a 5% deviation level. The parameter sets were then systematically optimized using sensitivity analysis, and a revised AMBER95 set was found to reproduce the crystal structures with less than 5% deviation from experiment. The stability of the various crystalline forms for each of the parameter sets (original and revised) was then assessed in extended MD simulations at 298 K and 1 bar covering 1 ns simulation time. The AMBER95 parameter sets (original and revised) were found to be effective in reproducing the crystal structures in these more stringent tests. Remarkably, the performance of the original AMBER95 parameter set was found to be slightly better than that of the revised set in these simulations at 298 K. The results of this study suggest that, whenever feasible, one should include molecular simulations at elevated temperatures when optimizing parameters

Topics: Force Field, Mannitol, Sorbitol, Crystalline Forms
Year: 2009
DOI identifier: 10.1021/jp9052665
OAI identifier: oai:bradscholars.brad.ac.uk:10454/4625
Provided by: Bradford Scholars
Download PDF:
Sorry, we are unable to provide the full text but you may find it at the following location(s):
  • http://hdl.handle.net/10454/46... (external link)
  • http://dx.doi.org/10.1021/jp90... (external link)
  • Suggested articles


    To submit an update or takedown request for this paper, please submit an Update/Correction/Removal Request.