title: Heterodimetallic germanium(IV) complex structures with transition metals.
abstract: The hydrothermal synthesis and structural characterization of a number of complex compounds containing the divalent tris(oxalato-O,O')germanate anion, [Ge(C2O4)3]2-, or the neutral bis(oxalate-O,O')germanium fragment, [Ge(C2O4)2], with transition-metal (M) cationic complexes of 1,10'-phenanthroline (phen) is reported: [M(phen)3][Ge(C2O4)3].xH2O [where M2+ = Cu2+ (1a and 1b), Fe2+ (2a and 2b), Ni2+ (3), Co2+ (4); x = 0.2 for 2b], [MGe(phen)2(mu2-OH)2(C2O4)2] [where M2+ = Cd2+ (5) and Cu2+ (6)]. The isolation of two polymorphs with Cu2+ (1a and 1b) and other pseudo-polymorphs for Fe2+ (2a and 2b) was rationalized based on slightly different molar ratios for the starting materials. All compounds have been characterized using EDS, SEM, vibrational spectroscopy (FT-IR and FT-Raman), thermogravimetry, and CHN elemental composition and their structure determined on the basis of single-crystal X-ray diffraction studies. The crystal packing of the different chemical moieties for each series of compounds was discussed on the basis of the various intermolecular interactions present (strong C-H...pi and weak C-H...O hydrogen-bonding interactions, C-H...pi and pi-pi contacts).
authors.affiliation: Department of Chemistry, University of Aveiro, CICECO, Aveiro, Portugal.
authors.forename: Fa-Nian
authors.initials: FN
authors.lastname: Shi
authors.forename: Luís
authors.initials: L
authors.lastname: Cunha-Silva
authors.forename: Michaele J
authors.initials: MJ
authors.lastname: Hardie
authors.forename: Tito
authors.initials: T
authors.lastname: Trindade
authors.forename: Filipe A Almeida
authors.initials: FA
authors.lastname: Paz
authors.forename: João
authors.initials: J
authors.lastname: Rocha