CePt₂Al₂: Structural and Bulk Properties

This work is focused on the structural and physical properties of CePt₂Al₂, an intermetallic compound. At room temperature, the modulated orthorhombic structure Cmme(a00)000, with $$= (0.481, 0, 0) has been determined by single-crystal X-ray diffraction supplemented by dependence of lattice parameters above room temperature for which the X-ray powder diffraction was used. The compound undergoes a structural transition to a tetragonal structure above room temperature. This transition exhibits 50 °C hysteresis and creates a domain structure in the sample. The magnetic behavior has been studied by specific heat, magnetization, and transport measurements in the temperature range between 0.5 and 300 K. Specific heat and susceptibility shows an antiferromagnetic order below 2 K. On the basis of electrical resistivity and other bulk measurements, CePt₂Al₂ can be considered a Kondo lattice material. The presence of a modulated crystal structure opens the possibility of a charge density wave state in CePt₂Al₂ as observed for (Re)Pt₂Si₂.