Hydroxo bridged dinuclear rare earth complexes: Syntheses and crystal structures of [Ln(2)(phen)(4)(H2O)(4)(OH)(2)](NO3)(4)(phen)(2) with Ln = Er, Lu

Reactions of phenanthroline (phen) and Er(NO3)(3) . 5 H2O or Lu(NO3)(3) . H 2O in CH3OH/H2O yield [Ln(2)(phen)(4)(H2O)(4)(OH)(2)](NO3)(4)(phen)(2) with Ln = Er (1), Lu (2). Both isostructural complex compounds crystallize in t he triclinic space. group P (1) over bar (no. 2) with the cell dimensions: a = 11.257(2) Angstrom, b = 11.467(2) Angstrom, c = 14.069(2) Angstrom, alp ha = 93.93(2)degrees, beta = 98.18(1)degrees, gamma = 108.14(l)degrees, V = 1696.0(6) Angstrom (3), Z = 1 for (1) and alpha = 11. 251(1) Angstrom, b = 11.476(1) Angstrom, c = 14.019(1) Angstrom, alpha = 93.83(1)degrees, beta = 98.27(1)degrees, gamma = 108.27(1)degrees, V = 1689.0(3) Angstrom (3), Z = 1 for (2). The crystal structures consist of the hydroxo bridged dinuclea r [Ln(2)(phen)(4)(H2O)(4)-(OH)(2) ](4+) complex cations, hydrogen bonded NO 3- anions and pi-pi stacking (phen)(2) dimers. The rare earth metal atoms a re coordinated by four N atoms of two phen ligands and four O atoms of two H2O molecules and two mu -OH groups to complete tetragonal antiprisms. Via two common mu -OH Cr groups, two neighboring tetragonal antiprisms are cond ensed to a centrosymmetric dinuclear [Ln(2)(phen)(4)(H2O)(4)(OH)(2)](4+) co mplex cation. Based on pi-pi stacking interactions and hydrogen bonding, th e complex cations and (phen)(2) dimers form 2 D layers parallel to (10 (1) over bar), between which the hydrogen bonded NO3- anions are sandwiched. Th e structures can be simplified into a distorted CsCl structure when {[Ln(2) (phen)(4)(H2O)(4)(OH)(2)](NO3)(4)} and (phen)(2) are viewed as building uni ts.