Cyanide-Bridged Iron(II,III) Cube with Multistepped Redox Behavior

Abstract

A building unit of Prussian blue was isolated as a cyanide-bridged iron cube of [Fe(II)4Fe(III)4(CN)12(tp)8] x 12 DMF x 2 Et2O x 4 H2O [tp(-) = hydrotris(pyrazolyl)borate]. A cyclic voltammogram showed quasi-reversible four-stepped redox waves, which correspond to [Fe(III)4Fe(II)4]/[Fe(III)5Fe(II)3](+), [Fe(III)5Fe(II)3](+)/[Fe(III)6Fe(II)2](2+), [Fe(III)6Fe(II)2](2+)/[Fe(III)7Fe(II)1](3+), and [Fe(III)7Fe(II)1](3+)/[Fe(III)8](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 Fe(III) ions, respectively, in the cube.

Effect of alkali cations on heterogeneous photo-Fenton process mediated by Prussian blue colloids

“…Finally, it has been commonly accepted that the photodriven charge-transfer reaction for Prussian blue under irradiation is the intervalence charge-transfer reaction [54,43,56,57], denoted as follows…”

Optical Activity and Dehydration-Driven Switching of Magnetic Properties in Enantiopure Cyanido-Bridged CoII3WV2 Trigonal Bipyramids

“…23 The CN − -bridged molecules adopt various discrete topologies controlled by a range of blocking ligands. 24 This includes trinuclear M 2 M′, 25,26 tetranuclear M 2 M′ 2 , 27,28 octanuclear M 4 M′ 4 , 29,30 pentanuclear M 3 M′ 2 , 31 and pentadecanuclear M 9 M′ 6 clusters. 32 −35 Among them, special attention is paid to trigonal-bipyramidal (TBP) M 3 M′ 2 clusters, realized by two axial polycyanidometallates forming bridges to three equatorial metal centers of octahedral geometry with four coordination sites blocked by chelating ligands.…”

Synthesis, structures, electrochemistry and magnetic properties of a cyano-bridged {Fe2Co2} molecular square

“…On the other hand, Prussian blue derivatives often show a very rich and diverse electrochemistry, as a result of the moderately strong electronic coupling interactions that have been observed in many ordered arrays and grid-type complexes [18]. Recently, Oshio and coworkers have been working on various cyanidebridged molecular squares with specific molecular functions, such as two-step spin-crossover and multistep redox behavior [19,20]. In order to better understand the role played by both the coordination sphere and the topology of FeCo based compounds, we have also devoted some efforts to the preparation of other low dimensional derivatives with tunable metal ion surroundings.…”