Thermal expansion of CuInTe2 from 30 to 300 K

Abstract

The thermal expansion coefficients αa and αc of the lattire parameters a and c of CuInTe2, are measured in the temperature range from 30 to 300 K using the X-ray Bond metohod. Both αa and αc decrease with decreasing tcmperature and become negative at about 38 and 54 K, respectively. The results are discussed in terms of the principal Grüneisen parameters of chalcopyrite structure crystals. It is concluded that there are low-energy lattice vibrational modes with negative Grüneisen parameters in CuInTe2. A comparison is mde with previous measurements for CuInTe2, and other Cu–III–VI2 compounds as well as with theoretical estimates.