Short- and medium range order in GeTe4-Ag glasses

Short- and medium range order glasses of GeTe4-Ag approximate composition have been studied by neutron diffraction, X-ray diffraction and extended X-ray absorption fine structure spectroscopy. Chemical correlations have been determined by fitting multiple datasets simultaneously with the reverse Monte Carlo simulation technique. It has been found that Ge atoms remain basically fourfold coordinated by Te while Te atoms have mostly two Ge/Te neighbours. The topology of the GeTe4 host network does not change upon adding Ag. Similarly to binary Ge-Te glasses, neighbouring GeTe4 tetrahedra are predominantly in corner sharing configuration in all investigated GeTe4-Ag compositions. Ag atoms bind mostly to Te and the average total coordination number of Ag does not change significantly with increasing Ag content.