Water displacement by cyanogold complexes in binuclear nickel(II) compounds based on bridging oxalate. Synthesis, structural diversity, magnetic properties, and DFT calculations
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Updated: Sep 27, 2026
Effect of Microwave Synthesis Conditions on the Structure of Nickel Hydroxide Nanosheets
Published on: August 18, 2023
Pablo Vitoria1, Iñaki Muga, Juan M Gutiérrez-Zorrilla
1Departamento de Química Inorgánica, Facultad de Ciencias, Universidad del País Vasco, Apartado 644, E-48080 Bilbao, Spain.
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.
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