Order-disorder phase transition and dissociation of hydrogen sulfide under high pressure: ab initio molecular dynamics study.
The structural and dynamical properties of phase IV and V of hydrogen sulfide were investigated by means of extensive ab initio molecular dynamics simulations. Starting from an experimental proposal for the structure of phase IV, an Ibca symmetry with a stable hydrogen bonding network is found at 15 GPa and 100 K. Molecular dynamics simulations at increasing temperature and at the pressure of 15 GPa suggest that phase IV will transform to a proton disordered structure at 15 GPa and 350 K. The newfound structure has a hexagonal lattice of P63/mmc symmetry, which is believed to be the remaining crystalline structure of phase V. The high mobility of protons in phase V is believed to be the key point to the dissociation and decomposition of hydrogen sulfide.
Wang
Liancheng
L
State Key Laboratory of Superhard Materials, College of Physics, Jilin University, Changchun 130012, People's Republic of China.
Tian
Fubo
F
Feng
Wanxiang
W
Chen
Changbo
C
He
Zhi
Z
Ma
Yanming
Y
Cui
Tian
T
Liu
Bingbing
B
Zou
Guangtian
G