Spectroscopic and electrochemical properties of mononuclear Mn(III) complex and of binuclear di-μ-oxo bridged Mn(III) and Mn(IV) complex with isocyclam

Manganese (III/IV) μ‐Oxo Dimers and Manganese (III) Monomers with Tetraaza Macrocyclic Ligands and Historically Relevant Open‐Chain Ligands

“…The absorbance band at 548 nm was attributed to the d‐d transition of a Mn(III) ion within a mixed‐valence complex. In addition, the absorbance band at 562 nm corresponded to the d‐d transition of the Mn(IV) ion, and the absorbance band at 652 nm was a characteristic feature of a LMCT from oxo→Mn(IV) (as previously assigned by others) [15h,26] . A broad absorption band of low energy was observed in the visible and near IR range and assigned as an intervalence transfer between the Mn(III) and Mn(IV) ions, which set this compound as a Robin and Day class II.…”

“…The IR spectrum of complex 10 exhibited a strong Mn 2 O 2 vibration at 684 nm À 1 . [26] Cyclic voltammetry measurements of complex 10 revealed two quasi-reversible redox couples at E 1/2 = 0.29 and 1.09 V vs. NHE. Although both were somewhat ill-defined, the couples were assigned as Mn III,IV /Mn III,III and Mn III,IV /Mn IV,IV , respectively.…”

“…A broad absorption band of low energy was observed in the visible and near IR range and assigned as an intervalence transfer between the Mn(III) and Mn(IV) ions, which set this compound as a Robin and Day class II. The IR spectrum of complex 10 exhibited a strong Mn 2 O 2 vibration at 684 nm −1 [26] . Cyclic voltammetry measurements of complex 10 revealed two quasi ‐reversible redox couples at E 1/2 =0.29 and 1.09 V vs. NHE.…”

Efficient single-strand cleavage of DNA mediated by a MnIIIMnIV-based artificial nuclease

“…† The multinuclear character is confirmed by a broad absorption of low energy in the visible-near infrared range arising from the intervalence transition metal-metal band. We can conclude that 1 in aqueous solution is a binuclear di-µ-oxo Mn III /Mn IV complex due to the similarity to spectra recorded previously, 31 which is also consistent with the above ESI-MS spectral result.…”

“…† These two redox couples exist independently from each other: both the first and second redox couples are seen on voltammetric curves recorded in shorter potential ranges: from 0.8 to 0.2 V and from 0.2 to −0.5 V, respectively, which suggested the first redox couple to one-electron reversible oxidation of [Mn III Mn IV L 2 (µ-O) 2 ] + to [Mn IV Mn IV L 2 (µ-O) 2 ] 2+ and the second redox couple to one-electron reversible reduction of [Mn III Mn IV L 2 (µ-O) 2 ] + ion to [Mn III Mn III L 2 (µ-O) 2 ]. 31…”