A building unit of Prussian blue was isolated as a cyanide-bridged iron cube of [FeII4FeIII4(CN) 12(tp)8]·12DMF·2Et2O· 4H2O [tp- = hydrotris(pyrazolyl)borate]. A cyclic voltammogram showed quasi-reversible four-stepped redox waves, which correspond to [FeIII4FeII4]/[Fe III5FeII3]+, [Fe III5FeII3]+/[Fe III6FeII2]2+, [Fe III6FeII2]2+/[Fe III7FeII1]3+, and [FeIII7FeII1]3+/[Fe III8]4+ processes. Controlled potential absorption spectral measurements revealed two intervalence charge-transfer bands at 816 and 1000 nm, which were assigned to charge transfers from Fe II ions to adjacent and remote FeIII ions, respectively, in the cube.
ASJC Scopus subject areas
- Physical and Theoretical Chemistry
- Inorganic Chemistry