Structural and magnetic properties of the binuclear [Co2{(OPPh2)2N}4] complex: Ferromagnetic coupling between the two S=3/2 Co(II) ions

• Published in: Inorganic chemistry communications 2009-07, Vol.12 (7), p.615-618
• Main Authors: Ferentinos, Eleftherios, Chatziefthimiou, Spyros D., Robertson, Neil, Kyritsis, Panayotis
• Format: Article
• Language: English
• Subjects: Binuclear complex; Cobalt; Ferromagnetic coupling; Tetraphenylimidodiphosphinic acid
• ISSN: 1387-7003; 1879-0259
• DOI: 10.1016/j.inoche.2009.05.001

The coordination of [(OPPh2)2N]− to Co(II) affords a binuclear [Co2{(OPPh2)2N}4] complex. The analysis of the magnetic properties of this system is consistent with an unusual ferromagnetic interaction, in a binuclear Co(II) system, between the two S=3/2 Co(II) ions. The reaction between Co(II) and the deprotonated tetraphenylimidodiphosphinic acid, [(OPPh2)2N]−, afforded a binuclear [Co2{(OPPh2)2N}4] complex, as revealed by X-ray crystallography. The structure contains two monometallic biconnective [(OPPh2)2N]− ligands, with an averaged Co−O bond length of 2.008Å. The other two [(OPPh2)2N]− act as bimetallic triconnective ligands, forming two oxygen atom bridges, with the four Co−O(bridging) distances averaged at 2.155Å, and the two Co−O(non-bridging) distances at 1.973Å. The two approximately trigonal bipyramidal Co(II) ions are at a Co⋯Co distance of 3.301Å. The analysis of the magnetic properties of [Co2{(OPPh2)2N}4] is consistent with an unusual ferromagnetic interaction, in a binuclear Co(II) system, between the two S=3/2 Co(II) ions.