title: Blocking and bridging ligands direct the structure and magnetic properties of dimers of pentacoordinate nickel(II).
abstract: Dinuclear pentacoordinate nickel(ii) complexes of the formula [(NiTp*)2(μ-L)] (Tp* = hydrotris(3,5-dimethylpyrazolyl)borate; L = oxalate (); oxamate (); oxamidate (); OC(4-Cl-C6H4N)C(4-Cl-C6H4N)O ()) and {[Ni(N3-mc)]2(μ-L)}(PF6)2 (N3-mc = 2,4,4-trimethyl-1,5,9-triazacyclododec-1-ene; L = oxalate (); oxamate ()) have been synthesized and spectroscopically characterized (IR, (1)H NMR). X-ray structures of show nickel(ii) in a square pyramidal geometry and different supramolecular interactions. Magnetic measurements for show strong antiferromagnetic interactions across the bridging ligand [: J = -36.8 cm(-1), g = 2.16; : J = -43.6 cm(-1), g = 2.12; : J = -51.1 cm(-1), g = 2.12; : J = -39.7 cm(-1), g = 2.18; : J = -35.4 cm(-1), g = 2.20; : J = -44.3 cm(-1), g = 2.18]. Magneto-structural correlations between the magnitude of the magnetic coupling and the different blocking ligands, the different bridging ligands, the distortion of the coordination environment of Ni(ii) and the planarity between the bridging ligand and the basal plane of the Ni(ii) environment have been established for all complexes.
authors.affiliation: Departamento de Química Inorgánica and Regional Campus of International Excellence (Campus Mare Nostrum), Universidad de Murcia, E-30071 Murcia, Spain. dsl@um.es.
authors.forename: Luisa
authors.initials: L
authors.lastname: López-Banet
authors.forename: M Dolores
authors.initials: MD
authors.lastname: Santana
authors.forename: Gabriel
authors.initials: G
authors.lastname: García
authors.forename: José
authors.initials: J
authors.lastname: Pérez
authors.forename: Luís
authors.initials: L
authors.lastname: García
authors.forename: Luis
authors.initials: L
authors.lastname: Lezama
authors.forename: Iván
authors.initials: I
authors.lastname: da Silva