Abstrakt
A new ternary compound, U(9)Fe(7)Ge(24), was synthesized by arc-melting the elements, followed by annealing at 900 degrees C. This compound was characterized by single crystal and powder X-ray diffraction, magnetization, specific heat and electrical transport measurements.
It crystallizes in an original tetragonal structure type (space group 14/mmm), with lattice parameters a = 12.3789(2) angstrom and c = 18.2881(3) angstrom. Three uranium, eighth germanium, and three iron crystallographic sites exist in this structure, with the atoms making a stacking of infinite chains along the a and b axis.
From their interatomic distances strong interactions between the uranium and germanium atoms can be predicted. The magnetic and specific heat measurements down to 2 K do not show any magnetic transition.
The Curie Weiss behaviour with a negative paramagnetic Curie temperature theta p = -94 K and reduced effective magnetic moment of mu(eff) = 2.13 mu(B)/U indicate that the compound is rather far from onset of magnetism, presumably due to a strong hybridisation of the 5f and ligand states. The electrical transport measurements show a metallic behaviour. (C) 2010 Elsevier Ltd.
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