New ternary compounds in the Sm–Rh–Ge system

Abstract

Investigations made by powder X-ray diffraction on new (SmRh2Ge and Sm2Rh3Ge) and known (Sm2RhGe2 and Sm3Rh2Ge2) ternary compounds are reported. The SmRh2Ge compound (a=0.5553(1)nm, c=1.5520(2)nm) crystallizes in the hexagonal CeNi3-type structure (space group P63/mmc, No. 194). The Sm2Rh3Ge compound (a=0.5558(1)nm, c=1.2001(2)nm) crystallizes in the trigonal TbFe2-type structure (space group R3bm, No. 166-2). The Sm2RhGe2 compound (a=1.0649(3)nm, b=1.0940(3)nm, c=0.4323(3) nm, γ=122.25(2)°) crystallizes in the monoclinic Zr2CoSi2-type structure (space group B2/m, No. 12-1). The Sm3Rh2Ge2 compound (a=0.5597(1)nm, b=0.7919(1)nm, c=1.3308(2)nm) crystallizes in the ortorhombic La3Ni2Ga2-type structure (space group Pbcm, No. 57).