First-Principles Simulations of Liquid Water Using a Dielectric-Dependent Hybrid Functional

Abstract

We carried out first-principles simulations of liquid water under ambient conditions using a dielectric-dependent hybrid functional, where the fraction of exact exchange is set equal to the inverse of the high-frequency dielectric constant of the liquid. We found excellent agreement with experiment for the oxygen-oxygen partial correlation function at the experimental equilibrium density and 311 ± 3 K. Other structural and dynamical properties, such as the diffusion coefficient, molecular dipole moments, and vibrational spectra, are also in good agreement with experiment. Our results, together with previous findings on electronic properties of the liquid with the same functional, show that the dielectric-dependent hybrid functional accurately describes both the structural and electronic properties of liquid water.

Picture of the wet electron: a localized transient state in liquid water

“…48 There is ample evidence in the literature concerning the reliability of hybrid functionals similar to the one used in this work for the treatment of aqueous systems. [49][50][51][52] The van der Waals interactions are described through the nonlocal rVV10 functional, 53,54 in which the parameter b is set to 5.3 to correctly reproduce the experimental mass density of liquid water. 55 We take advantage of the implementation provided in the CP2K suite of codes.…”

Dissociation of salts in water under pressure

“…First principles molecular dynamics simulations (FPMD) were carried out using the Qbox code 46 coupled with the SSAGES suite of codes in client-server mode 47,48 . We used the PBE functional 49 , plane wave basis sets and optimized norm-conserving Vanderbilt (ONCV) pseudopotentials 50,51 , with an energy cutoff of 60 Ry to expand the electronic wave functions 52 . We modeled a NaCl solution of concentratioñ 0.68 M using a periodic cubic cell of volume (13.46 Å) 3 containing 126 (80) water molecules and 1 NaCl formula unit at 1000 K and 11 GPa (400 K and 1 atm).…”

Solvent–Adsorbate Interactions and Adsorbate-Specific Solvent Structure in Carbon Dioxide Reduction on a Stepped Cu Surface

“…We also emphasize here that understanding the accuracy and applicability of DFT for the structure and properties of liquid water is also an active research area. 34,[106][107][108][109][110] These considerations motivate further study of the effects of thermal energy on solvation structure near adsorbates.…”