The stannide CeZnSn was obtained in X-ray-pure form by induction-melting of the elements in a sealed tantalum ampoule. CeZnSn crystallizes with the YPtAs-type structure, space group P6 3 /mmc, a = 456.7(3), c = 1673.8(5) pm, wR2 = 0.0862, 259 F 2 values, and 12 variables. The zinc and tin atoms build up puckered Zn 3 Sn 3 hexagons (Zn-Sn 271 pm) with weak interlayer Zn-Zn interactions (323 pm). Susceptibility measurements of CeZnSn reveal modified Curie-Weiss behavior above 50 K with an experimental magnetic moment of 2.77(1) µ B / Ce atom. The cerium magnetic moments order ferromagnetically at T C = 5.2(1) K. 119 Sn Mössbauer spectra show a single tin site at an isomer shift of δ = 1.967(4) mm/s subjected to a small quadrupole splitting of ∆E Q = 0.41(2) mm/s at 40 K. At 4.2 K a magnetic hyperfine field of 0.872(5) T is transferred to the tin site. From DFT scalar relativistic calculations of the electronic and magnetic structures, chemical bonding analysis reveals on one hand a weaker bonding of Zn than of Sn with the cerium substructures with a twice stronger Ce1-Sn bond compared to Ce2-Sn. On the other hand, a ferromagnetic ground state is identified from total energy differences in agreement with experiment.

La 5 Cu 4 As 4 O 4 Cl 2 was prepared from a cold-pressed pellet of lanthanum filings, ground arsenic, Cu 2 O and LaOCl in the ideal 3 : 4 : 2 : 2 ratio. The pellet was annealed in an evacuated silica tube at 1473 K for two days and then cooled down to room temperature. LaOCl was always observed as a by-product. La 5 Cu 4 As 4 O 4 Cl 2 crystallizes with a new structure type: I4/mmm, a = 413.46 (7), c = 4144 (1)

The magnesium compounds RE 4 Co 2 Mg 3 (RE = Pr, Gd, Tb, Dy) were prepared by induction melting of the elements in sealed tantalum tubes. The samples were studied by powder X-ray diffraction. The structures of the gadolinium and of the terbium compound were refined from single crystal diffractometer data:

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The rare earth-rich intermetallic magnesium compounds RE 4 PdMg (RE = Y, Sm, Gd) and RE 4 PtMg (RE = Y, Nd, Sm, Gd) were prepared by melting of the elements in sealed tantalum tubes in an induction furnace. These new Gd 4 RhIn-type compounds were characterized by X-ray powder diffraction. The structures of the gadolinium compounds were refined from single crystal X-ray diffractometer data: space group F43m, Z = 16, a = 1388.1(2) pm, wR2 = 0.0392, 381 F 2 values and 20 variables for Gd 4 Pd 1.14 Mg 0.86 and a = 1387.6(2) pm, wR2 = 0.0519, 409 F 2 values, BASF = 0.47(4) and 21 variables for Gd 4 Pt 1.07 Mg 0.93 . The gadolinium atoms build up palladium (platinum) centered trigonal prisms which are condensed via common corners and edges, leading to three-dimensional networks. The magnesium atoms form Mg 4 tetrahedra which show slight mixing with the platinum metal.