New metal-rich compounds RE23Pt7Mg4 (RE = La, Ce, Pr, Nd, Sm)

作者：Linsinger Stefan; Eul Matthias; Poettgen Rainer

来源：Intermetallics, 2010, 18(5): 889-892.

DOI：10.1016/j.intermet.2009.12.028

• Intermetallics
• miscellaneous
• Crystal chemistry of intermetallics
• Magnetic properties

The rare earth metal-rich magnesium compounds RE23Pt7Mg4 (RE = La, Ce, Pr, Nd, Sm) were synthesized by induction melting of the elements in sealed tantalum tubes. The samples were studied by powder Xray diffraction. The structure of Nd23Pt7Mg4 was refined from single crystal X-ray diffractometer data: Pr23Ir7Mg4 type, P6(3)mc, hP68, Z = 2, a = 1003.8(4), c = 2265.0(8) pm, wR2 = 0.0529, 2337 F-2 values, 74 variables. Striking structural motifs of the RE23Pt7Mg4 compounds are platinum centered trigonal prisms of the rare earth atoms and Mg-4 tetrahedral cluster units. The trigonal prisms are condensed via common edges and corners, leading to rigid three-dimensional networks. Magnetic susceptibility measurements of Pr23Pt7Mg4 show Curie Weiss behaviour with an experimental magnetic moment of 3.56(1) mu(B)/Pr atom. Pr23Pt7Mg4 orders antiferromagnetically at a Neel temperature of T-N = 5.4(5) K.

• 出版日期2010-5