Valence structures and magnetic interactions of 1-D mixed-metal complexes, [Ni1−xPdxX(chxn)2]X2 (0.0 ≤ x ≤ 1.0, chxn = (1R,2R)-diaminocyclohexane; X = Cl, Br) studied by 15N solid-state NMR

We performed natural-abundance 15N NMR spectroscopy measurements on 1-D mixed-metal complexes, [Ni1−xPdxX(chxn)2]X2 (0.0 ≤ x ≤ 1.0, chxn = (1R,2R)-diaminocyclohexane; X = Cl, Br). The spectra obtained for 15N bonded directly not only to Pd2+and Pd4+, but also to Pd3+, and Ni3+ could be separated from each other more clearly than those obtained previously through 13C NMR measurements. From the results obtained, a spin structure model in which several Pd2+ and Pd4+ sites next to Ni3+ sites in 1-D chains are converted into paramagnetic Pd3+ was shown, and the conversion ratio into Pd3+ was estimated.