Intermediate-valent Yb4Rh7Sb6 with cubic U4Re7Si6 type structure

TLDR: In this article, the structure was refined on the basis of single crystal X-ray diffractometer data: U 4 Re 7 Si 6 type, Im3m, a = 865.9(2) pm, wR2 = 0.0557, 159 F 2 values and 10 variables.

Abstract: Yb 4 Rh 7 Sb 6 was synthesized by arc-melting ofthe elements. The structure was refined on the basis of single crystal X-ray diffractometer data: U 4 Re 7 Si 6 type, Im3m, a = 865.9(2) pm, wR2 = 0.0557, 159 F 2 values and 10 variables. The two crystallographically independent rhodium atoms have octahedral and tetrahedral antimony coordination with Rh-Sb distances ranging from 269 to 274 pm. These polyhedra are condensed via common edges and comers, leading to a complex three-dimensional [Rh 7 Sb 6] network. Coordination number 12 cavities within this network are filled by the ytterbium atoms. Temperature dependent magnetic susceptibility measurements show modified Curie-Weiss behavior and an experimental magnetic moment of 3.16(1) μ B /Yb atom, pointing to intermediate-valent ytterbium. Magnetization measurements at 5 K give hint for short-range magnetic ordering. 121 Sb Mossbauer spectra confirm the single crystallographic antimony site and antimonide character.