Lattice temperature and hyperfine interactions of Pb1?xSnxTe (0.21 ≤ x ≤ 0.75)

Thin (<15 μm) samples of lead tin telluride, Pb_1?xSn_xTe (x = 0.21, 0.25, 0.55, and 0.75) have been studied by temperature dependent Mössbauer spectroscopy using the 23.8 keV gamma radiation of ^119mSn. The tin atom occupies a lattice site having cubic symmetry (QS = 0 ± 0.020 mm sec^?1) over the temperature range 78 ≤ T ≤ 240 K, and there is no evidence for a rhombic (low temperature) to cubic (high temperature) phase transition such as that reported for SnTe in this temperature interval. The lattice temperature as probed by the Sn atom is independent of the compositional parameter x and is similar to that reported for SnTe from Mössbauer studies and for Pb_0.63Sn_0.37Te from X-ray powder diffraction data. Radiation damage produced by 2-MeV proton irradiation to a total fluence of ～10¹⁷ cm^?2 at liquid nitrogen temperature does not have any effect on the Mössbauer parameters, possibly because the major damage is annealed at temperatures below 150 K.