DFTB-MD Simulation of Shocked Water Cluster

Relatively efficient and precise quantum molecular dynamics simulations were performed to gain fundamental insights into the mechanisms for the primary detonation process of water under shock wave loading using self-consistent charge density-functional tight binding (SCC-DFTB) calculations combined with the multiscale shock technique (MSST) as well as DFTB+ program conjunct with MSST. We observe that water achieves chemical equilibrium in less than 4ps for all shock conditions studied. What’s more, we make comparison with the experimental results for the Hugoniot pressure and density final states. At last, our simulations show that decomposition occurs through the reversible H2O↔H+OH , in agreement with experiment. Therefore, the molecular dynamics method of water under extreme conditions is effective.