The title compound [Co(IM2-Py)(PCA)(N-3)(2)] (IM2-Py = 2-(2'-pyridyl)-4,4,5,5-tetramdthylimidazoline-1-oxyl, PCA 2-pyridine carboxylic acid) has been prepared and structurally characterized by elemental analysis, IR spectra and X-ray,diffraction. It crystallizes in monoclinic, space group P2(1)/c with a 13.169(3), b = 11.235(2), c = 15.596(3)Angstrom, beta = 104.70(3)degrees, V = 2232.0(8) Angstrom(3), C18H21CoN10O3, M-r = 484.38, Z = 4, D-c = 1.441 g/cm(3) mu(MoKalpha) = 0.8 11 mm(-1), F(000) = 1000, the final R = 0.0563 and wR = 0.1010. The nitronyl nitroxide (NIT2Py) was reduced to IM2-Py. and another NIT2Py oxidated to PCA. The self-redox reaction between the radicals was observed. The cobalt(H) ion is gix-coordinated into a distorted octahedral geometry. Meanwhile, the intermolecular cobalt(H) ion is gix-coordinated into a distorted octahe hydrogen bonds result in the dimer.