The structure of As3Se5Te2 infrared optical glass

The structure of As3Se5Te2 infrared optical glass was investigated by X-ray and neutron diffraction as well as extended X-ray absorption fine structure measurements at the As-, Se- and Te K-edges. The five datasets were modelled simultaneously by the reverse Monte Carlo simulation technique. Experimental data could be fitted satisfactorily by allowing As–Se, As–Te and Se–Te bonds only. It was revealed that the affinity of As is much higher to Se than to Te. The nearest As–Se distance is similar to that found in other vitreous As–Se based alloys, while the As–Te bond length is 0.02–0.04 Å shorter in As3Se5Te2 than in binary As–Te glasses.