Intermediate-range order in liquid and amorphous As2S3 by ab initio molecular-dynamics simulations

Abstract The structural properties of liquid and amorphous As2S3 are investigated by means of ab initio molecular-dynamics simulations. It is shown that the first-sharp diffraction peak (FSDP) exists at about k=1.2 A−1 in the calculated structure factor for lower densities, and disappears under pressure, which is in agreement with the experimental observations. The effects of hydrostatic compression on the local atomic configuration are investigated in detail, and the relation between the structural change and the density dependence of the first-sharp diffraction peak is discussed.