Abstract

van der Waals (vdW) correction schemes have been recognized to be essential for an accurate description of liquid water in first-principles molecular dynamics simulation. The description of the structure and dynamics of water is governed by the type of the vdW corrections. So far, two vdW correction schemes have been often used: empirical vdW corrections and nonlocal vdW corrections. In this paper, we assess the influence of the empirical vs nonlocal vdW correction schemes on the structure and dynamics of water at the water–air interface. Since the structure of water at the water–air interface is established by a delicate balance of hydrogen bond formation and breaking, the simulation at the water–air interface provides a unique platform to testify as to the heterogeneous interaction of water. We used the metrics [Ohto et al. J. Chem. Theory Comput., 2019, 15, 595−60230468702] which are directly connected with the sum-frequency generation spectroscopic measurement. We find that the overall performance of nonlocal vdW methods is either similar or worse compared to the empirical vdW methods. We also investigated the performance of the optB88-DRSLL functional, which showed slightly less accuracy than the revPBE-D3 method. We conclude that the revPBE-D3 method shows the best performance for describing the interfacial water.

Highlights

  • ABSTRACT: van der Waals correction schemes have been recognized to be essential for an accurate description of liquid water in first-principles molecular dynamics simulation

  • First-principles molecular dynamics (FPMD) simulations performed with the generalized gradient approximation (GGA)-XC or hybrid GGA-XC functionals erroneously predict the properties of water

  • The frequently used nl-van der Waals (vdW) correction schemes are DRSLL20,21 and rVV10.22,23 The nonlocal vdW (nl-vdW) corrections were combined with various GGA XC functionals based on eq 2.9,24−28 The DRSLL nl-vdW corrections have been used for predicting the property of bulk water.[25,26]

Read more

Summary

INTRODUCTION

Van der Waals (vdW) interactions are essential for predicting structure and dynamics of water in the bulk and at the interface.[1,2] the density functional theory (DFT) itself is rigorous, the approximated exchange-correlation (XC) functionals within the generalized gradient approximation (GGA) or hybrid GGA cannot compute the vdW interaction energy accurately. FPMD simulations based on the GGA-XC functionals without vdW corrections underestimated the bulk density of water. The frequently used nl-vdW correction schemes are DRSLL20,21 and rVV10.22,23 The nl-vdW corrections were combined with various GGA XC functionals based on eq 2.9,24−28 The DRSLL nl-vdW corrections have been used for predicting the property of bulk water.[25,26] the optB88-DRSLL29 was suggested as one of the best DFT methods for computing the water properties.[1,9,24,30,31] the water properties in the bulk and at the interface predicted with the nl-vdW correction schemes have not been rigorously compared with those with the empirical vdW corrections. This indicates that the empirical vdW correction schemes are adequate to improve the description of interfacial water in FPMD simulation at the GGA level of theory

VDW CORRECTIONS
Nonlocal vdW Density Functional Correction
SIMULATION PROTOCOLS
TARGET QUANTITIES
RESULTS
CONCLUSION
■ REFERENCES
Full Text
Published version (Free)

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call