Mixed Valency in Yb₇Co₄InGe₁₂:  A Novel Intermetallic Compound Stabilized in Liquid Indium

Abstract

The quaternary compounds RE7Co4InGe12 (RE = Dy, Ho, Yb) were obtained from In flux reactions as thin silver needles. RE7Co4InGe12 crystallizes in the tetragonal P4/m space group under a new structure type which is characterized by columnar units forming three different types of channels with the RE atoms situated within these channels. Investigation of the Yb analog with magnetic susceptibility measurements, X-ray photoelectron spectroscopy (XPS) and X-ray absorption near edge spectroscopy (XANES) revealed that Yb7Co4InGe12 is a mixed-valence compound and that the relative Yb3+/Yb2+ ratio is slightly temperature-dependent. Additionally, resistivity measurements for Yb7Co4InGe12 exhibited negative magnetoresistance at low temperatures.

Crystal structure and properties of tetragonal EuAg4In8 grown by metal flux technique

“…The use of indium flux has been proved to be an excellent tool to produce many novel ternary and quaternary intermetallic phases [45][46][47][48][49]. A few new polyindides with an impressive set of diverse structures and compositions have been synthesized using In as solvent [45,46]. The crystal structure of EuAg 4 In 8 was studied using single crystal X-ray diffraction data.…”

Crystal Structure and Properties of Yb5Ni4Ge10

“…[13] Within the Sc 5 Co 4 Si 10 type, no compounds have been reported with Ni as the transition element. One motivation for the work described here is the continued development of the intermetallic chemistry of Yb [14][15][16][17][18][19][20][21] and the deeper understanding of the ability of Yb to adopt different or mixed oxidation states. There are a few compounds reported within the Yb-Ni-Ge system.…”

New compounds and structures in the solid state

“…Interestingly the use of In as a solvent has also yielded compounds that are relatively In-poor; reaction in an excess of In has yielded the products Ln 7 Co 4 InGe 12 that provide the first examples of a new structure type. 58 These compounds again accommodate Ln within channels, although in these compounds the networks are composed of the 3-dimensional [Co 4 Ge 12 ] framework shown in Fig. 8.…”