Skip to main content
U.S. Department of Energy
Office of Scientific and Technical Information

Isobaric-isothermal Monte Carlo simulations from first principles: Application to liquid water at ambient conditions

Journal Article · · ChemPhysChem
OSTI ID:950083
A series of first principles Monte Carlo simulations in the isobaric-isothermal ensemble were carried out for liquid water at ambient conditions (T = 298 K and p = 1 atm). The Becke-Lee-Yang-Parr (BLYP) exchange and correlation energy functionals and norm-conserving Goedecker-Teter-Hutter (GTH) pseudopotentials were employed with the CP2K simulation package to examine systems consisting of 64 water molecules. The fluctuations in the system volume encountered in simulations in the isobaric-isothermal ensemble requires a reconsideration of the suitability of the typical charge density cutoff and the regular grid generation method previously used for the computation of the electrostatic energy in first principles simulations in the microcanonical or canonical ensembles. In particular, it is noted that a much higher cutoff is needed and that the most computationally efficient method of creating grids can result in poor simulations. Analysis of the simulation trajectories using a very large charge density cutoff at 1200 Ry and four different grid generation methods point to a substantially underestimated liquid density of about 0.85 g/cm{sup 3} resulting in a somewhat understructured liquid (with a value of about 2.7 for the height of the first peak in the oxygen/oxygen radial distribution function) for BLYP-GTH water at ambient conditions.
Research Organization:
Lawrence Livermore National Laboratory (LLNL), Livermore, CA
Sponsoring Organization:
USDOE
DOE Contract Number:
W-7405-ENG-48
OSTI ID:
950083
Report Number(s):
UCRL-JRNL-208389
Journal Information:
ChemPhysChem, Journal Name: ChemPhysChem Journal Issue: 9 Vol. 6; ISSN CPCHFT; ISSN 1439-4235
Country of Publication:
United States
Language:
English

Similar Records

Liquid Water from First Principles: Validation of Different Sampling Approaches
Journal Article · Thu May 20 00:00:00 EDT 2004 · Journal of Physical Chemistry B: Materials, Surfaces, Interfaces, amp Biophysical · OSTI ID:15014181

Toward a Monte Carlo program for simulating vapor-liquid phase equilibria from first principles
Journal Article · Wed Oct 20 00:00:00 EDT 2004 · Computer Physics Communication, vol. 169, no. 1-3, April 1, 2005, pp. 8 · OSTI ID:950086

Mass density fluctuations in quantum and classical descriptions of liquid water
Journal Article · Sun Jun 25 20:00:00 EDT 2017 · Journal of Chemical Physics · OSTI ID:1390421