Single-crystal growth of layered Ce-Ni-Ge ternary compounds

We have attempted to grow single crystals of Ce-Ni-Ge ternary system having layered structure. Several polycrystalline samples, CeNiGex (2 < x < 3), Ce3NixGey (1.6 < x < 2, 6.5 < y < 8.5) and Ce2NiGe6, were prepared by an arc-melting of constituent elements. All samples grown by the Czochralsky method are found to contain the phase of the orthorhombic CeNiGe2 type structure. A Rietveld method was applied to analyze the crystal structure of CeNiGe2.2 Using X-ray powder diffraction data at room temperature. The refined lattice parameters were a = 4.260 angstrom, b = 16.81 angstrom and c = 4.209 angstrom with the space group Cmmm. The temperature dependence of magnetic susceptibility shows a significant variation in the magnetic properties depending on the concentration of Ge, that is, magnetic phase transition temperature depends on starting materials. It may come from the fact that the magnetic property relies on a structural homogeneity and a stoichiometry. (c) 2005 Published by Elsevier B.V.