Structural, thermal, and electrical properties of CrSi2

Stoichiometric CrSi2 was prepared by arc melting and compacted by uniaxial hot pressing for property measurements. The crystal structure of CrSi2 was investigated using the powder x-ray diffraction method. From the Rietveld refinement, the lattice parameters were found to be a=4.427 57 (7) and c=6.368 04 (11) A, respectively. The thermal expansion measurement revealed an anisotropic expansion in the temperature range from room temperature 800 K with alpha(a)=14.58x10(-6)/K, alpha(c)=7.51x10(-6)/K, and alpha(V)=12.05x10(-6)/K. The volumetric thermal expansion coefficient shows an anomalous decrease in the temperature range of 450-600 K. The measured electrical resistivity rho and thermoelectric power S have similar trends with a maxima around 550 K. Thermal conductivity measurements show a monotonic decrease with increasing temperature from a room temperature value of 10 W m(-1) K-1. The ZT values increase with temperature and have a maximum value of 0.18 in the temperature range studied. An analysis of the electronic band structure is provided. (C) 2008 American Institute of Physics.