Synthesis and characterisation of uranium(IV) nitrate complexes with piperazines

Uranium(IV) complexes of empirical formula U(NO3)4L2 (L = piperazine, 1-methyl-, 2-methyl-, 1-phenyl-, 1,4-dimethyl-, 2,6-dimethyl-, or 2,5-dimethyl-piperazine) have been prepared by a new method involving the in situ reaction of uranium(IV) nitrate with the ligands. Infrared spectral studies indicate the nitrate groups to be co-ordinated in a chelating bidentate fashion and the piperazines in a chair conformation. The electronic spectra and magnetic properties are also discussed. (author)