Transition Metal-centered Trigonal Prisms as BuildingUnits in RE14T3In3 (RE = Y, Ho, Er, Tm, Lu; T = Pd, Ir, Pt) and Y4IrIn

Abstract

The indides RE14T3In3 (RE = Y, Ho, Er, Tm, Lu; T = Pd, Ir, Pt) and Y4IrIn were synthesized from the elements by arc-melting and subsequent annealing for crystal growth. Their structures were characterized on the basis of X-ray powder and single crystal data: Lu14Co3In3-type, space group P42/nmc, a = 970.2(1), c = 2340.7(5) pm for Y13.95Pd3In3.05, a = 959.7(1), c = 2309.0(5) pm for Ho14Pd2.95In3, a = 955.5(1), c = 2305.1(5) pm for Er14Pd3In3, a = 950.9(1), c = 2291.6(5) pm for Tm13.90Pd3In3.10, a = 944.4(1), c = 2275.5(5) pm for Lu13.93Pd3In3.07, a = 962.9(1), c = 2343.0(5) pm for Y13.86Ir2.97In3.02, a = 967.6(1), c = 2347.8(5) pm for Y13.92Pt3.05In2.91, and Gd4RhIn-type, space group F 4̅3m, a = 1368.6(2) pm for Y4IrIn. The main structural motifs are transition metal-centered trigonal prisms of the rare earth elements which are condensed to twodimensional networks in the RE14T3In3 indides and to a three-dimensional one in Y4IrIn. The indium atoms in both structure types show segregation in the metal-rich matrix, i. e. In2 dumbbells in the RE14T3In3 indides (309 pm In2-In2 in Y13.86Ir2.97In3.02) and In4 tetrahedra (322 pm In-In) in Y4IrIn. The crystal chemical peculiarities of both structure types are discussed.