DEHYDRATION OF LANTHANIDE HALIDES HYDRATES - CRYSTAL-STRUCTURE OF [CE(MU-CL)(3)(THF)(H2O)]INFINITY - A BIDIMENSIONAL MESH-LIKE POLYMER

The title compound was obtained by segregation of the mixed-metal Ce-T i species formed in THF by reacting Ti(OEt)(4) and the cerium chloride ethanol-adduct resulting from dehydration of CeCl3 . 7H(2)O by ethylo rthoformate. The overall structure is based on a bidimensional meshlik e polymer. Each CeCl3(THF)(H2O) unit is connected to three others by d ouble halide bridges which make infinite chains spreading out along th e a and b axis. These layers are stacked along c. Each cerium atom is surrounded by six chlorine atoms [2.819(1) to 2.927(1) Angstrom] and t wo oxygens of the THF and water ligands [2.530(3) and 2.495(3) Angstro m]. The overall stereochemistry of the 8-coordinate metal is that of a n antiprism. Intermolecular H-bonds are observed between the water and chlorine ligands, O-H ... Cl 3.11-3.28 Angstrom within and between th e layers.