Atomic-scale structure of GeSe₂ glass revisited: A continuous or broken network of Ge-(Se_1/2)₄ tetrahedra?

The atomic-scale structure of germanium diselenide (GeSe₂) glass has been revisited using a combination of high-energy x-ray diffraction and constrained reverse Monte Carlo simulations. The study shows that the glass structure may be very well described in terms of a continuous network of corner-and edge-sharing Ge-Se₄ tetrahedra. The result is in contrast to other recent studies asserting that the chemical order and, hence, network integrity in GeSe₂ glass are intrinsically broken. It is suggested that more elaborate studies are necessary to resolve the controversy.