Local Structure Analysis in $Ab$ $Initio$ Liquid Water

Abstract

Within the framework of density functional theory, the inclusion of exact exchange and non-local van der Waals/dispersion (vdW) interactions is crucial for predicting a microscopic structure of ambient liquid water that quantitatively agrees with experiment. In this work, we have used the local structure index (LSI) order parameter to analyze the local structure in such highly accurate $ab$ $initio$ liquid water. At ambient conditions, the LSI probability distribution, P($I$), was unimodal with most water molecules characterized by more disordered high-density-like local environments. With thermal excitations removed, the resultant bimodal P($I$) in the inherent potential energy surface (IPES) exhibited a 3:1 ratio between high- and low-density-like molecules, with the latter forming small connected clusters amid the predominant population. By considering the spatial correlations and hydrogen bond network topologies $among$ water molecules with the same LSI identities, we demonstrate that the signatures of the experimentally observed low- (LDA) and high-density (HDA) amorphous phases of ice are present in the IPES of ambient liquid water. Analysis of the LSI autocorrelation function uncovered a persistence time of $\sim$ 4 ps---a finding consistent with the fact that natural thermal fluctuations are responsible for transitions between these distinct yet transient local aqueous environments in ambient liquid water.

12 pages, 6 figures

References in corpus (8)

• Quantum ESPRESSO: a modular and open-source software project for quantum simulations of materials
• Nuclear quantum effects in water
• Self-consistent hybrid functional for condensed systems
• The Individual and Collective Effects of Exact Exchange and Dispersion Interactions on the Ab Initio Structure of Liquid Water
• On the accuracy of DFT exchange-correlation functionals for H bonds in small water clusters II: The water hexamer and van der Waals interactions
• Order-N implementation of exact exchange in extended systems
• Isobaric first-principles molecular dynamics of liquid water with nonlocal van der Waals interactions
• Coupled cluster benchmarks of water monomers and dimers extracted from DFT liquid water: the importance of monomer deformations

Cited by in corpus (23)

• Advanced capabilities for materials modelling with Quantum ESPRESSO
• Perspective: How good is DFT for water?
• The hydrogen bond network of water supports propagating optical phonon-like modes
• Distinct signature of two local structural motifs of liquid water in the scattering function
• Structural, Electronic, and Dynamical Properties of Liquid Water by ab initio Molecular Dynamics based on SCAN Functional within the Canonical Ensemble
• Isotope Effects in Liquid Water via Deep Potential Molecular Dynamics
• Unravelling the contribution of local structures to the anomalies of water: the synergistic action of several factors
• Viscosity in water from first-principles and deep-neural-network simulations
• Enabling Large-Scale Condensed-Phase Hybrid Density Functional Theory Based $Ab$ $Initio$ Molecular Dynamics I: Theory, Algorithm, and Performance
• A local order metric for condensed phase environments
• Network Topology in Water Nanoconfined between Phospholipid Membranes
• The physics of Empty Liquids: from Patchy particles to Water
• Searching for crystal-ice domains in amorphous ices
• Structural and topological changes across the liquid-liquid transition in water
• Decoding the Competing Effects of Dynamic Solvation Structures on Nuclear Magnetic Resonance Chemical Shifts of Battery Electrolytes via Machine Learning
• Self-Interaction Correction in Water-Ion Clusters
• Enabling Large-Scale Condensed-Phase Hybrid Density Functional Theory Based $Ab$ $Initio$ Molecular Dynamics II: Extensions to the Isobaric-Isoenthalpic and Isobaric-Isothermal Ensembles
• Diffusion-Oscillatory Dynamics in Liquid Water on Data of Dielectric Spectroscopy
• High-Throughput Condensed-Phase Hybrid Density Functional Theory for Large-Scale Finite-Gap Systems: The SeA Approach
• Isotope effects in x-ray absorption spectra of liquid water
• Speeding-up Hybrid Functional based Ab Initio Molecular Dynamics using Multiple Time-stepping and Resonance Free Thermostat
• Manifestations of the structural origin of supercooled water's anomalies in the heterogeneous relaxation on the potential energy landscape
• Statistical mechanical theory of liquid water