Spin state solvomorphism in a series of rare S = 1 manganese(III) complexes

Structural, magnetic and spectroscopic data of four complex salts, [Mn(napsal₂323)]NTf₂, 1,[Mn(napsal₂323)]ClO₄, 2, [Mn(napsal₂323)]BF₄, 3 and [Mn(napsal₂323)]NO₃, 4, of the [Mn(napsal₂323)]⁺ complex cation indicate that the Mn³⁺ ion is stabilized in the rare S = 1 spin triplet form in this ligand sphere. Zero-field splitting values of D = +19.6 cm⁻¹ and |E| = 2.02 cm⁻¹ for complex 1 were obtained by High Field Electron Paramagnetic Resonance (HFEPR) measurements conducted over a range of frequencies. Structural and magnetic data also indicate that co-crystallization of complexes 2 and 3 with 0.5 equivalents of ethanol yields the high spin S = 2 forms of the perchlorate and tetrafluoroborate solvates [Mn(napsal₂323)]ClO₄·0.5(C₂H₅OH), 2·0.5EtOH and [Mn(napsal₂323)]BF₄·0.5(C₂H₅OH), 3·0.5EtOH.