Superconductivity in 122 antimonide SrPt2Sb2

Measurements of electrical resistivity ρ, magnetization M and specific heat C have revealed that SrPt2Sb2 is a type-II superconducting material with a superconducting critical temperature (Tc) of 2.1 K. The electronic specific heat coefficient γ and the ratio ΔC(Tc)/γTc are 9.2(1) mJ mol−1 K−2 and 1.29, respectively. The temperature dependence of ρ exhibits anomalies around 270 K. Synchrotron x-ray diffraction patterns at 295 and 134 K clearly indicate that SrPt2Sb2 undergoes a structural phase transition in the temperature range from 134 to 295 K, suggesting that the anomalies observed in ρ around 270 K are related to a structural phase transition.