Crystal structure, thermal expansion and electrical properties of GdCo0.67Ga1.33 compound

A new ternary compound GdCo0.67Ga1.33 was synthesized and its crystal structure was determined by the Rietveld refinement of X-ray powder diffraction data. This compound crystallizes in the orthorhombic, space group Imma (No. 74) with the CeCu2 structure type, and a=0.43625(2) nm, b=0.70935(3) nm, c=0.75705(4) nm, Z=4 and Dcalc=8.207 g/cm3. The thermal expansion of GdCo0.67Ga1.33 was studied by high temperature powder X-ray diffraction technique in the temperature range of 301-598 K. The volumetric coefficient of thermal expansion, αV, can be represented by αV(T)=4.73×10−6+8.45×10−8T. The Debye temperature of GdCo0.67Ga1.33 is calculated to be ΘD=261.6 K. The electrical properties of this compound were measured between 5 and 300 K. Temperature variations of electrical resistivity suggest that magnetic ordering occurs at low temperature. The residual resistivity ratio RRR of the compound is about 1.2.