Structural chemistry of mixed-ligand inorganic fluoride complexes of uranyl (review)

Abstract

The crystal structures of mixed-l igand sulfato-, selenato-, phosphato-, arsenato-, and chromato-fluoride complexes of uranyl studied by the single-c rystal X-ray diffraction method have been systematized and discussed. The crystal chemical features of the structures of the mixed-ligand inorganic fluoride complexes of uranyl were determined: the coordination polyhedron of the hexavalent uranium atom in the structures of the mixed-ligand inorganic fluoride complexes of uranyl has a pentagonal-bipyramidal structure: the oxygen atoms of the uranyl group are located on the vertical axis of the pentagonal bipyramid, perpendicular to the equatorial plane in which five atoms are located. In the crystal structures of dimeric and polymeric chain mixed-ligand inorganic fluoride complexes of uranyl the fluoride bridges form fluoride atoms. Inorganic ligands combine dimers and polymeric chains into layers and three-d imensional formation.