Abstract

Ab initio molecular dynamics simulations of liquid GeSe2 show that the first sharp diffraction peak in the concentration-concentration structure factor S-CC(k) is due to a sequence of connected fourfold rings. These subunits can be viewed as chains of edge-sharing tetrahedra. Ge atoms at the opposite tails of these chains are mostly miscoordinated and separated from each other by intermediate range distances. This result correlates a specific structural subunit to a subtle intermediate range order property, involving both the structural and chemical composition of the disordered network.

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