The solution optical and NMR spectra of (TPP)MnX (X = F-, NCO, CH3CO2", HCO2", N3", Cl", Br, NO2", NO3", NCS", CN-, I", C104", BF4", B(C6H5)4-) indicate that ionic bonding may be particularly important in manganese tetraphenylporphyrin complexes. A Karplus-Fraenkel equation utilization of 13C NMR spectra for the calculation of electron spin densities at the porphyrin nuclei uncovers an unexpectedly high positive density at the pyrrole -carbon sites. The densities for the acetato, nitrato, and perchlorate complexes are 0.049, 0.056, and 0.063, respectively. Such high densities are unlikely to be covalent in origin, and accordingly an axial ligand dependent mixture of the [Mnn(S = 3/2,4A2)P(S = *l/2,2 2)•"]+ + [Mnm(S = 2,5Ai)P2"]+ electronic states is proposed for the ground valence state of manganese tetraphenylporphyrin complexes. The calculations probably underestimate the -carbon spin densities, so the C2v (d^,^)0 (d^)1 (dxz dyz)2 (dxy)2 (a2(vr))1 (3 ( ))2 [MnnP,-]+ valence state is likely to be the principal ground-state contributor. The electron spin at the -carbon sites dominates the carbon-13 spectroscopy through polarization and correlation. In contrast to previous deductions of negative ( ) density, but in accord with the hyperporphyrin optical spectra, a high positive ( ) density is present at the meso sites. This spin density is effectively undermined by the greater spin at the -carbon location. The phenyl residue NMR reflects an axial ligand dependent balance of spin polarization and positive spin delocalization from the meso position. The