Kondo insulator description of spin state transition in FeSb2 -: art. no. 045103

The thermal expansion and heat capacity of FeSb2 at ambient pressure agrees with a picture of a temperature induced spin state transition within the Fe t(2g) multiplet. However, high pressure powder diffraction data show no sign of a structural phase transition up to 7 GPa. A bulk modulus B=84(3) GPa has been extracted and the temperature dependence of the Gruneisen parameter has been determined. We discuss here the relevance of a Kondo insulator description for this material.