Synthesis and single crystal study of CuMn3As2 and Cu2Mn4As3.

We report on single-crystal growth, and crystal structure of CuMn 3 As 2 and Cu 2 Mn 4 As 3 compounds. Magnetic properties of Cu 2 Mn 4 As 3 were studied in temperature range between 2 and 400 K. The single crystals were prepared from bismuth flux and characterized by means of single crystals diffraction, electron-microprobe analysis, magnetic and resistivity measurements. Crystal structures of CuMn 3 As 2 and Cu 2 Mn 4 As 3 were determined by synchrotron radiation x-ray diffraction experiments at 100 K. The CuMn 3 As 2 and Cu 2 Mn 4 As 3 crystallize in an orthorhombic structure with very similar lattice parameters. Magnetic and resistivity measurements on Cu 2 Mn 4 As 3 suggest existence of long range magnetic order below 315 K with another magnetic transition at 45 K. [ABSTRACT FROM AUTHOR]