Synthesis, crystal structure and some physical properties of RuZn3

Abstract

The crystal structure, phase relations and some physical properties of the binary zinc-rich phase RuZn₃ are reported. The title compound is accessible via high-temperature reaction from the elements in the appropriate substance amount ratio. Its crystal structure was determined from a Rietveld profile fit to an X-ray diffractogram of pristine RuZn₃ and confirmed by single-crystal X-ray structure analysis. The title compound adopts a tetragonal Al₃Zr-type structure corresponding to an A²B² anti-phase domain structure of the cubic AuCu₃-type: a = 376.82(3) pm, c = 1554.78(13) pm, I4/mmm, Z = 4, R(F)(all data) = 0.0197, 153 unique reflections, 12 variables. The structure is discussed in the light of the Hume-Rothery concept. RuZn₃ melts at 1373(2) K, is a moderate metallic conductor (ρ(293 K) = 6.2 mΩ cm) and exhibits basically temperature-independent paramagnetic properties. It coexists with Ru_1−xZn_x and RuZn₆.