Structural, magnetic, and thermal characteristics of the phase transitions in Gd5Ga x Ge4− x magnetocaloric materials

Temperature-dependent, single crystal and powder X-ray diffraction studies as well as magnetization, and heat capacity measurements were carried out on two phases of the Gd5Ga x Ge4− x system: for x=0.7 and 1.0. Gd5Ga0.7Ge3.3 shows three structure types as a function of temperature: (i) from 165K to room temperature, the orthorhombic Sm5Ge4-type structure exists; (ii) below 150K, it transforms to a orthorhombic Gd5Si4-type structure; and (iii) …