Isobaric-Isothermal Molecular Dynamics Simulations Utilizing Density Functional Theory: An Assessment of the Structure and Density of Water at Near-Ambient Conditions

September 3, 2009

Journal Article

Isobaric-Isothermal Molecular Dynamics Simulations Utilizing Density Functional Theory: An Assessment of the Structure and Density of Water at Near-Ambient Conditions

Abstract

We present herein, a comprehensive density functional theory study towards assessing the accuracy of two popular gradient corrected exchange correlation functionals on the structure and density of liquid water at near ambient conditions in the isobaric-isotherma ensemble. Our results indicate that both PBE and BLYP functionals underpredict the density and overstructure the liquid. Adding the dispersion correction due to Grimme [1, 2] improves the predicted densities for both BLYP and PBE in a significant manner. Moreover, the addition of the dispersion correction for BLYP yields an oxygen-oxygen radial distribution function in excellent agreement with experiment. Thus, we conclude that one can obtain a very satisfactory model for water using BLYP and a correction for dispersion. This work was supported by the U.S. Department of Energy's (DOE) Office of Basic Energy Sciences, Chemical Sciences program, and was performed in part using the Molecular Science Computing Facility (MSCF) in the William R. Wiley Environmental Molecular Sciences Laboratory, a DOE national scientific user facility located at the Pacific Northwest National Laboratory (PNNL). PNNL is operated by Battelle for DOE.

Revised: September 30, 2009 | Published: September 3, 2009

Citation

Schmidt J., J. VandeVondele, I.W. Kuo, D. Sebastiani, J.L. Siepmann, j. hutter, and C.J. Mundy. 2009. Isobaric-Isothermal Molecular Dynamics Simulations Utilizing Density Functional Theory: An Assessment of the Structure and Density of Water at Near-Ambient Conditions. Journal of Physical Chemistry B 113, no. 35:11959-11964. PNNL-SA-65066.