Molecular Dynamics Study of α-Ag₂S

Abstract

Superionic conductor α-Ag₂S is simulated by the molecular dynamics with a simple ionic potential. The simulations are performed for two systems, one with 384 ions (128 S ions and 256 Ag ions) and the other with 1296 ions (432 S ions and 864 Ag ions). The simulated results show a characteristic feature of α-AgI type superionic conductor: anions form a bcc lattice and cations are mobile among interstitial sites. The temperature dependence of the tracer diffusion constant of Ag ions and the Debye-Wallar factor of S ions are in good agreement with experimentally observed ones. The velocity autocorrelation functions and the electrical conductivity are also obtained.