Crystal structure of U(VI) phthalate dihydrate [UO2(OOC) 2C6H4·H2O]·H 2O

Crystalline uranyl phthalate dihydrate was prepared by hydrothermal method, and its crystal structure was determined. The crystal structure consists of infinite chains [UO2LH2O]n coupled in bands [(UO2)2L2(H2O)2] n [L = C6H4(COO)2], between which water molecules of crystallization are located. The coordination polyhedron of uranium atoms is a pentagonal bipyramid with the equatorial plane formed by oxygen atoms of three phthalate ions and coordinated water molecule. The U-O bond length in the UO 2 2+ cations is 1.766 Å. The coordination capacity of the ligands is 4. Anions are bidentately coordinated to uranium atoms to form seven-membered rings. Being bridging ligands, phthalate ions combine the neighboring uranium atoms into chains through one carboxy group, and the chains into bands, through the other carboxy group. © 2004 MAIK Nauka/Interperiodica"."