A neutron diffraction study of glassy GeS2

The total structure factor for glassy GeS2 was measured by using neutron di ffraction. The possibility of broken chemical ordering was then explored by interpreting the results in terms of recently measured partial pair distri bution functions for the corresponding diselenide glass GeSe2 which show a significant number of homopolar bonds. It was found that the latter do not give an accurate account of the nearest-neighbour correlations in the disul phide glass and no compelling evidence could be found for a substantial dev iation from heteropolar Ge-S bonding. (C) 2001 Elsevier Science B.V. All ri ghts reserved.