Observation of Intramolecular Paramagnetic T1 Spin Decoupling in the 13C NMR Spectra of Triazacyclohexane Complexes of Ni(II)

N-Benzyl-substituted complexes [(triazacyclohexane)Ni(NCMe)3](BF4)2 and their diamagnetic zinc analogues have been prepared and characterized by X-ray crystallography. The T1 spin decoupling observed in their paramagnetic 13C NMR spectra can be quantitatively described by newly derived expressions that allow an independent determination of T2 of the 13C signal, T1 of the attached H or F, and the 1J coupling constant by line shape analysis.