Cobalt complexes with picolinic acid (HPic), namely, [Co-II(Pic)(2)(H2O)] .
2H(2)O (I) and [COIII(Pic)(3)] . H2O (II) are studied using H-1 and C-13 N
MR spectroscopy. Compound I exists in solution as three geometric isomers,
namely, trans-trans-trans, cis-trans-cis, and trans-cis-cis (molar ratio 4
: 2 : 1, respectively). According to C-13 NMR data, compound II exists in s
olution as a mer-isomer. The relative energy stability of the isomers was e
stimated using the molecular mechanics method.