Molecular and electronic structure changes during successive reduction of a
Fe-tetraphenylporphyrin chloride [Fe(III)(TPP):Cl] complex are reported on the basis of Mössbauer spectroscopy
and DFT calculations. It is established that the attachment of additional electrons to a neutral Fe(III)(TPP):Cl
molecule leads to signifi cant shortening of Fe-N distances at the fi rst stage of the reduction Fe(III)(TPP):Cl →Fe(II)(TPP) and lengthening of these bonds at the second stage Fe(II)(TPP)→Fe(I)(TPP). Changes of other
bond lengths of the porphyrin ring also appear but in less degree. Interaction of Fe(II) and Fe(I)(TPP) with tetrahydrofuran
(THF) solvent is considered. Electron configuration of Fe(II)(TPP) corresponds to intermediate-spin
(S = 1) state and in the case of Fe(I)(TPP) low-spin state (S = ½) is observed. Electron density distribution in
Fe(II)- and Fe(I)(TPP) complexes, in association with Mössbauer data, is analyzed. Good correlation between
experimental and theoretical results was obtained