Simulating Raman spectra of hydrogen hydrates using first-principles path-integral ring-polymer molecular dynamics

Abstract

A variant of first-principles (FP) path-integral ring-polymer molecular dynamics (RPMD) simulations was used to investigate the C0,C1, and C2 H2 hydrates at 280 K aiming at reproducing their experimental Raman spectra. We find that our implementation based on white-noise Langevin thermostat applied to the H2O sub-system only in the formulation of FP-RPMD is able to reproduce with high accuracy the characteristic features of the measured Raman spectra of H2 hydrates in all C0,C1, and C2 phases, demonstrating potential of our computational approach for investigating H-containing materials under pressure.