New Arsenide Yb2Cu4As3: Crystal Structure and Electronic State of Ytterbium

A new arsenide of composition Yb2Cu4As3 was prepared by elemental synthesis, and its structure was determined by x-ray diffraction (Rietveld powder-diffraction analysis, 118 independent reflections, RI = 0.064, Rp = 0.097): Hf2Co4P3 type, sp. gr. P\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document} $$\overline 6 $$ \end{document}2m, a = 1.33072(3) nm, c = 0.40091(1) nm. Magnetic susceptibility measurements and EXAFS data indicate that Yb2Cu4As3 contains roughly equal amounts of Yb2+ (4f14 configuration) and Yb3+ (4f13).