Intercalative Ion Exchange of Polyamine Transition Metal Complexes into Hydrogen Uranyl Phosphate

A series of derivatives of hydrogen uranyl phosphate (HUP) was prepared by displacing the butylammonium ions of butylammonium uranyl phosphate with the transition metal complexes Cu(en)(2)(2+), Cu(pn)(2)(2+), Cu(trien)(2+), Cu(14-ane)(2+), Cu(15-ane)(2+), Ni(trien)(2+), Ni(14-ane)(2+), and Ni(diene)(2+). X-ray powder patterns proved that the original tetragonal structure of the UP layers remained intact in all derivatives. The extent of the ion exchange and the interlamellar distances were found to depend mainly on the size and on the shape of a particular coordinating ligand. Electronic absorption spectra indicated that the intercalated complexes had four-coordinate square-planar geometry inside the UP lattice. Extents of hydration of the intercalates varied significantly, and they depended mostly on the shapes of the coordinating ligands and on their abilities to regularly pack between the UP layers. Results of the above-mentioned characteristics allow one to divide these transition metal complexes into two groups which differ from each other in their abilities to efficiently fill up the space between the UP layers. The steady-state luminescence spectra of intercalates showed a very weak uranyl emission which was partly due to quenching by the Cu(2+) and Ni(2+) guest complexes and partly to self-absorption.