Crystal structure of Yb2CuGe6 and Yb 3Cu4Ge4 and the valency of ytterbium

Sebastian C. Peter, Udumula Subbarao, Sumanta Sarkar, G. Vaitheeswaran, Axel Svane, Mercouri G. Kanatzidis

Research output: Contribution to journalArticle

16 Citations (Scopus)

Abstract

The Yb2CuGe6 and Yb3Cu4Ge 4 compounds were synthesized from reaction mixtures using indium as flux. Both powder and single crystal X-ray diffraction data were used to refine the crystal structures. Yb2CuGe6 crystallizes in the monoclinic space group C2/m in the La2AlGe6 type structure. The lattice parameters are a = 8.0011(16) Å, b = 8.1962(16) Å, c = 10.682(2) Å and β = 100.63(3). The crystal structure of Yb2CuGe6 can be described as the intergrowth of fragments Ge dimmers and zig-zag Ge chains. Yb3Cu4Ge4 crystallizes in the orthorhombic space group Immm in the Gd3Cu 4Ge4 type structure. The lattice parameters are a = 4.1302(8) Å, b = 6.5985(13) Å and c = 13.691(3) Å. X-ray absorption near edge spectroscopy (XANES) measurements indicate that Yb in Yb2CuGe6 and Yb3Cu4Ge4 exists as intermediate and trivalent states, respectively. The structural refinement of Yb2CuGe6 is corroborated by total energy calculations within the local density approximation.

Original languageEnglish
Pages (from-to)405-411
Number of pages7
JournalJournal of Alloys and Compounds
Volume589
DOIs
Publication statusPublished - Mar 15 2014

    Fingerprint

Keywords

  • Crystal growth
  • Crystal structure
  • Electronic structure
  • Metal flux technique
  • Valence
  • X-ray diffraction

ASJC Scopus subject areas

  • Mechanics of Materials
  • Mechanical Engineering
  • Metals and Alloys
  • Materials Chemistry

Cite this