First-principles molecular dynamics simulations of single nitrogen bond structures in a N2H2 system under pressure. (March 2019) - Zhong, Xin
Abstract: The search of single nitrogen bond phases is of fundamental interest since they are potential high energy content materials. Recently, several experiments have reported the existence of a novel NH phase with single nitrogen bonds. However, there is no detailed information on the structures and the mechanism on its formation. In this work, formation of the NH phase was investigated employing first-principles molecular dynamics at high pressure and room temperature. The results reveal that N2 reacts readily with H2 molecules under moderate pressure at room temperature. The resulting compound is composed mainly of single NN bonds. The calculated vibrational density of state at 50 GPa is in good agreement with the experimental Raman spectrum. The theoretical results offer insights into the understanding of the polymeric mechanism in nitrogen compounds. Highlights: The single nitrogen bond network structure composed of N2 with H2 molecules. The calculated VDOS is in good agreement with experimental Raman data. The N2 and H2 can react at room temperature and high pressure without catalyst.