Carbon-1 3 nuclear magnetic resonance spectra of a series of trans-diacido( 1 ,lO-diamino-4,7-dia~aadecane)cobalt(III) complexes (truns-Co(3,2,3-tet)X2, X = Br-, C1-, N3-, NH,, NO2-, OAc) and trans-diacido( 1,9-diamino-3,7-diazanonane)cobalt(III) complexes (trans-Co(2,3,2-tet)X2, X = C1-, GlyH, -OAc, NH,, NO2-) will be discussed. The "C chemical shift is found to be linearly dependent on the ligand field strength (estimated from the electronic spectrum) of the axial ligands (X). The shielding of selected carbon atoms within the tetraamine ligand, which has been attributed to the central metal ion, increases with increasing axial ligand field strength.