(NH(4))(2)[UO(2)Cl(4)]·2H(2)O, a new uranyl tetra­chloride with ammonium charge-balancing cations

A new uranyl tetra­chloride salt with chemical formula, (NH(4))(2)[UO(2)Cl(4)]·2H(2)O, namely, di­ammonium uranyl tetra­chloride dihydrate, 1, was prepared and crystallized via slow evaporation from a solution of 2 M hydro­chloric acid. As confirmed by powder X-ray diffraction, the title compound crystallizes with an ammonium chloride impurity that formed as a result of the breakdown of a triazine precursor. The (UO(2)Cl(4))(2−) dianion is charge balanced by ammonium cations, while an extensive hydrogen-bond network donated from structural water mol­ecules stabilize the overall assembly. Compound 1 adds to the extensive collection of actinyl tetra­chloride salts, but it represents the first without an alkali cation for purely inorganic compounds. Diffuse reflectance and luminescence spectra show typical absorption and emission behavior, respectively, of uranyl materials.