Two-dimensional lanthanide coordination polymers with bis(diphenylphosphino)hexane dioxide. The determination of the polymeric structure from twinned crystals

Lanthanide nitrates and bis(diphenylphosphino)hexane dioxide (dpphO(2)) formed under solvothermal conditions a series of coordination polymers [Ln(dpphO(2))(2)(NO3)(2)](NO3) (Ln = Pr (1), Nd (2), Sin (3), Dy (4), Lu (5)), featuring two-dimensional network structure of the (4,4) topology. The compounds [Ln(dpphO(2))(2)Cl-2]Cl (Ln = Pr (6), Nd (7), Gd (8)) were obtained from corresponding chlorides. Coordination polymer 7 formed regular single crystals of the orthorhombic Pna2(1) space group. The nitrate complexes crystallized in the orthorhombic Aea2 space group, however, the crystals were pseudo-merohedral twins simulating a tetragonal diffraction pattern. Unlike our previously characterized neutral polymers with bis(diphenylphosphino)ethane dioxide, all present coordination networks are cationic, with anions located between or within the two-dimensional layers. (C) 2007 Elsevier Ltd. All rights reserved.