116891-10-2Relevant articles and documents
Cobalt(II) Triazene 1-Oxide Bis(chelates). A Case of Planar (Low Spin)-Tetrahedral (High Spin) Isomerism
Wolny, Juliusz A.,Rudolf, Mikolaj F.,Ciunik, Zbigniew,Gatner, Kazimierz,Wolowiec, Stanislaw
, p. 1611 - 1622 (2007/10/02)
High- and low-spin cobalt(II) triazene 1-oxide bis(chelates) have been isolated.The low-spin complexes possess square-planar structure whilst the high-spin complexes are tetrahedral.The molecular structure of high-spin has been determined: triclinic, space group P , Z = 2, a = 7.970(5), b = 10.174(5), c = 11.676(5) Angstroem, α = 87.18(4), β = 74.31(4) and γ = 74.06(4) deg.For some complexes the isolation of both planar (low-spin) and tetrahedral (high-spin) isomers or of their conglomerates is possible depending on the synthesis conditions.The crystal structure of square-planar , which is isomorphous with the low-spin isomer of , has been determined: triclinic, space group Pa = 7.495(2), b = 7.694(5), c = 8.612(3) Angstroem, α = 64.64(5), β = 87.84(2) and γ = 78.64(3) deg.The complexes exhibit a planar-tetrahedral equilibrium in non-co-ordinating solvents, the ΔH and ΔS values of which, determined from solution magnetic susceptibility measurements, are in the range 1-15kJ mol-1 and 5-30 JK-1mol-1, respectively.The electrochemical properties of the complexes are given.