2006/01/06 by Yujie Wu, Harald L. Tepper, Gregory A. Voth · 1,294 citations
Chemistry · Engineering · Physics and Astronomy · #Chemistry #Classical mechanics #Computational chemistry #Dielectric #Diffusion #Dipole #Hydrogen bond #Intermolecular force #Intramolecular force #Materials science #Molecular dynamics #Molecular geometry #Molecule #Nanopore and Nanochannel Transport Studies #Organic chemistry #Physics #Point particle #Spectroscopy and Quantum Chemical Studies #Theoretical and Computational Physics #Thermodynamics #Water model #Work (physics)
paper · doi:10.1063/1.2136877
published in The Journal of Chemical Physics 124(2), 024503 (American Institute of Physics)
openalex publication_date 2006/01/06 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/01
In order to introduce flexibility into the simple point-charge (SPC) water model, the impact of the intramolecular degrees of freedom on liquid properties was systematically studied in this work as a function of many possible parameter sets. It was found that the diffusion constant is extremely sensitive to the equilibrium bond length and that this effect is mainly due to the strength of intermolecular hydrogen bonds. The static dielectric constant was found to be very sensitive to the equilibrium bond angle via the distribution of intermolecular angles in the liquid: A larger bond angle will increase the angle formed by two molecular dipoles, which is particularly significant for the first solvation shell. This result is in agreement with the work of Hochtl et al. [J. Chem. Phys. 109, 4927 (1998)]. A new flexible simple point-charge water model was derived by optimizing bulk diffusion and dielectric constants to the experimental values via the equilibrium bond length and angle. Due to the large sensitivities, the parametrization only slightly perturbs the molecular geometry of the base SPC model. Extensive comparisons of thermodynamic, structural, and kinetic properties indicate that the new model is much improved over the standard SPC model and its overall performance is comparable to or even better than the extended SPC model.