On the synthesis of actinide complexes with neutral organic phosphorus compounds

The complexes of uranium (6) and (4) nitrates with trialkyl-phosphine oxides (TAPO) have been synthetized, and qeneral methods of their synthesis, separation and purification described. It has been found that, whatever the method of preparation, each compound of the synthesized homologous series of complexes corresponds only to disolvate stoichiometry of a qeneral formula, UO2(NO3)2 x 2(Csub(n)Hsub(2n+1))3PO and U(NO3)4 x 2(Csub(n)Hsub(2n+1))3PO. It is shown that the complexes prepared do not contain water and nitric acid. The absence of water and acid in the complex composition, as well as the possibility of preparing the same compounds by the methods where no nitric acid is used, make it possible to believe that formation of acidocomplexes is unlikely. The described methods pf complex synthesis may be of use for preparative and analytical purposes in separating (quantitatively, in some cases) complexes of actinide, rare-earth, noble, transplutonium, and other elements with phosphates, phosphinates, phosphine oxides, di- and polyoxides, as well as with other organic ligands. The experimental data on the thermal properties of the complexes separated are presented