The interaction of oligo(ethylene glycol) with water: Testing an atomisticforce field for transferability

Citation
Aj. Pertsin et al., The interaction of oligo(ethylene glycol) with water: Testing an atomisticforce field for transferability, PHYS CHEM P, 3(9), 2001, pp. 1598-1601
Citations number
15
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Physical Chemistry/Chemical Physics
Journal title
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
ISSN journal
1463-9076 → ACNP
Volume
3
Issue
9
Year of publication
2001
Pages
1598 - 1601
Database
ISI
SICI code
1463-9076(2001)3:9<1598:TIOOGW>2.0.ZU;2-B
Abstract
An atomistic force field fitted to ab initio MP2 level energies and geometr ies of 1,2-dimethoxyethane (EG1) and EG1-water complexes (D. Bedrov, M. Pek ny and G. D. Smith, J. Phys. Chem. B, 1998, 102, 996) is tested for transfe rability to methoxy terminated tri(ethylene glycol) (EG3) and its complexes with water. The test is based on a comparison of the force field predictio ns for EG3 and EG3-water complexes with the respective results of recent ab initio calculations using density functional theory (DFT) (R. L. C. Wang, H. J. Kreuzer and M. Grunze, Phys. Chem. Chem. Phys., 2000, 2, 3613). The f orce field well reproduces the structure and stability sequence of EG3 and EG3-water conformers but yields noticeably higher EG3-water binding energie s. Most of the difference in binding energy is associated with differences between the ab initio methods used in parametrization (MP2) and testing (DF T) of the force field. The agreement between the force field and ab initio DFT predictions can be improved by introducing an additional fitting parame ter, like dielectric permittivity, which attenuates the electrostatic terms of the EG3-water potential.