Benchmarking the performance of Density Functional Theory and Point Charge Force Fields in their Description of sI Methane Hydrate against Diffusion Monte Carlo

Abstract

High quality reference data from diffusion Monte Carlo calculations are presented for bulk sI methane hydrate, a complex crystal exhibiting both hydrogen-bond and dispersion dominated interactions. The performance of some commonly used exchange-correlation functionals and all-atom point charge force fields is evaluated. Our results show that none of the exchange-correlation functionals tested are sufficient to describe both the energetics and the structure of methane hydrate accurately, whilst the point charge force fields perform badly in their description of the cohesive energy but fair well for the dissociation energetics. By comparing to ice Ih, we show that a good prediction of the volume and cohesive energies for the hydrate relies primarily on an accurate description of the hydrogen bonded water framework, but that to correctly predict stability of the hydrate with respect to dissociation to ice Ih and methane gas, accuracy in the water-methane interaction is also required. Our results highlight the difficulty that density functional theory faces in describing both the hydrogen bonded water framework and the dispersion bound methane.

8 pages, 4 figures, 1 table. Minor typos corrected and clarification added in Methods

References in corpus (13)

• Quantum ESPRESSO: a modular and open-source software project for quantum simulations of materials
• Perspective: Advances and challenges in treating van der Waals dispersion forces in density functional theory
• Continuum variational and diffusion quantum Monte Carlo calculations
• Jastrow correlation factor for atoms, molecules, and solids
• On the accuracy of DFT exchange-correlation functionals for H bonds in small water clusters II: The water hexamer and van der Waals interactions
• The Finite Size Error in Many-body Simulations with long-Ranged Interactions
• To wet or not to wet? Dispersion forces tip the balance for water-ice on metals
• Smooth relativistic Hartree-Fock pseudopotentials for H to Ba and Lu to Hg
• Norm-conserving Hartree-Fock pseudopotentials and their asymptotic behavior
• Quantum Monte Carlo applied to solids
• Dissociation energy of the water dimer from Quantum Monte Carlo calculations
• Benchmarking the performance of Density Functional Theory and Point Charge Force Fields in their Description of sI Methane Hydrate against Diffusion Monte Carlo
• Quantum Monte Carlo, Density Functional Theory, and Pair Potential Studies of Solid Neon

Cited by in corpus (13)

• Simulation and understanding of quantum crystals
• Boosting the accuracy and speed of quantum Monte Carlo: size-consistency and time-step
• Properties of the water to boron nitride interaction: from zero to two dimensions with benchmark accuracy
• Benchmarking the performance of Density Functional Theory and Point Charge Force Fields in their Description of sI Methane Hydrate against Diffusion Monte Carlo
• Toward Accurate Adsorption Energetics on Clay Surfaces
• Systematic study of finite-size effects in quantum Monte Carlo calculations of real metallic systems
• Chemical accuracy from quantum Monte Carlo for the Benzene Dimer
• The nature of three-body interactions in DFT: exchange and polarization effects
• Random-Phase Approximation in Many-Body Noncovalent Systems: Methane in a Dodecahedral Water Cage
• Low-pressure phase diagram of crystalline benzene from quantum Monte Carlo
• Rapidly convergent quantum Monte Carlo using a Chebyshev projector
• Thermodynamical study of N${}_2$ clathrate hydrate from DFT calculations
• Noncovalent Interactions by QMC: Speedup by One-Particle Basis-Set Size Reduction