PREPARATION AND CHARACTERIZATION OF POTASSIUM, RUBIDIUM AND AMMONIUM TETRACHLOROURANATE(III) TRIHYDRATES

The synthesis and characterization of a new series of hydrated uranium(III) complex chlorides of the general formula M(I)UCl4.3H2O (M(I) = K, Rb or NH4) are reported. The compounds crystallize in the monoclinic system. Unit cell parameters were determined from X-ray powder diffraction data. The magnetic susceptibilities of the complex chlorides were measured by the Faraday method in the 4.2-300 K range. The compounds exhibit Curie-Weiss paramagnetism in the 100-300 K range, with the derived effective magnetic moments ranging from 3.57mu(B) to 3.71mu(B). Solid state electronic and IR spectra were recorded in the 4000-30 000 and 80-4000 cm-1 ranges, respectively and discussed. Non-static high vacuum thermal dehydrations enabled us to obtain the anhydrous compounds KUCl4, RbUCl4 and UCl3.