title: Water displacement by cyanogold complexes in binuclear nickel(II) compounds based on bridging oxalate. Synthesis, structural diversity, magnetic properties, and DFT calculations.
abstract: Several cyanogold complexes react with the binuclear nickel complex [(Ni(dien)(H(2)O))(2)(mu-ox)](PF(6))(2).2H(2)O to give the compounds [(Ni(dien)(H(2)O))(2)(mu-ox)]Br(2) (1), [(Ni(dien)(Au(CN)(2)))(2)(mu-ox)] (2), and [(Ni(dien))(2)(mu-ox)(mu-Au(CN)(4))](PF(6)) (3) (dien, diethilenetriamine; ox, oxalate). In the case of compounds 2 and 3, water displacement by the corresponding cyanogold complex takes place, whereas compound 1 is formed by a substitution of the anion. The crystal structures of compounds 1 and 2 present a 2D arrangement where the layers are connected by van der Waals forces (1) or N-H.Ntbd1;C hydrogen bonds (2), where each binuclear complex is hydrogen bonded to its neighbors, whereas compound 3 presents a novel structure where the tetracyanoaurate acts as a bridging ligand to give a polymeric compound. Magnetic studies of these compounds reveal an antiferromagnetic behavior. Finally, density functional theory (DFT) calculations have been performed on isolated models of compounds 2 and 3 in order to gain some insight about the different behavior of the [Au(CN)(2)](-) and [Au(CN)(4)](-) groups as ligands and proton acceptors in hydrogen bonds.
authors.affiliation: Departamento de Química Inorgánica, Facultad de Ciencias, Universidad del País Vasco, Apartado 644, E-48080 Bilbao, Spain.
authors.forename: Pablo
authors.initials: P
authors.lastname: Vitoria
authors.forename: Iñaki
authors.initials: I
authors.lastname: Muga
authors.forename: Juan M
authors.initials: JM
authors.lastname: Gutiérrez-Zorrilla
authors.forename: Antonio
authors.initials: A
authors.lastname: Luque
authors.forename: Pascual
authors.initials: P
authors.lastname: Román
authors.forename: Luis
authors.initials: L
authors.lastname: Lezama
authors.forename: F Javier
authors.initials: FJ
authors.lastname: Zúniga
authors.forename: Javier I
authors.initials: JI
authors.lastname: Beitia