Structure and properties of Ce3Pd3Bi4, CePdBi, and CePd2Zn3

Hermes W, Linsinger S, Mishra R, Pöttgen R

Zusammenfassung

The intermetallic cerium compounds Ce3-Pd3Bi4, CePdBi, and CePd2Zn3 were synthesized from the elements in sealed tantalum ampoules in an induction furnace. The compounds were characterized by X-ray powder and single crystal diffraction: CeCo3B2 type (ordered version of CaCu5), P6/mmm, a = 538.4(4), c = 427.7(4) pm, wR2 = 0.0540, 115 F 2 values, 9 variables for CePd2Zn3 and Y3Au3Sb4 type, I 4 3d, a = 1005.2(2) pm, w R2 = 0.0402, 264 F 2 values, 9 variables for Ce3Pd3Bi4, and MgAgAs type, a = 681.8(1) pm for CePdBi. The bismuthide structures are build up from three-dimensional networks of corner-sharing PdBi4 tetrahedra with Pd-Bi distances of 281 (Ce3Pd3Bi4) and 296 pm (CePdBi), respectively. The cerium atoms are located in larger voids of coordination number 12 (Ce3Pd3Bi4) and 10 (CePdBi). In CePd2Zn3 the cerium atoms fill larger channels within the three-dimensional [Pd2Zn3] network with 18 (6 Pd + 12 Zn) nearest neighbors. The three compounds contain stable trivalent cerium with experimental magnetic moments of μeff = 2.70(2), 2.48(1), and 2.49(1) μB/Ce atom for CePd2Zn3, Ce3Pd3Bi4, and CePdBi, respectively. Susceptibility and specific heat data gave no hint for magnetic ordering down to 2.1 K.