Ternary compounds Ce0.67Pt2Al5 and Ce1.33Pt3Al8

The ternary intermetallic compounds Ce0.67Pt2Al5 (I) and Ce1.33Pt3Al8 (II) were synthesized in the Ce-Pt-Al system by the reaction of elemental Ce, Pt, and Al in an arc furnace under an argon atmosphere. The crystal structures of I and II were determined from single-crystal X-ray diffraction data. The crystals are characterized by the following unit cell parameters: a = 4.3105(18) Å, c = 16.494(5) Å, space group P63/mmc, Z = 2 (I) and a = 4.361(2) Å, c = 39.00(2) Å, space group R3¯m, Z = 6 (II). Both compounds have structures with different packing of layers.