Diamagnetic iron

One-electron reduction of the iron(lll) alkyl complexes forms the diamagnetic iron(ll) alkyl anions [Fe(Por)R. The iron(ll) anions do not react with oxygen directly, but are first oxidized by O2 to the corresponding alkyliron(III) complexes, Fe(Por)R, which then insert O2 as described above. 

Magnetic Interaction in a Diamagnetic Iron Complex (Example [Fe02(SC6HF4)(TPpiyP)])... 

If the intersystem crossing rate with diamagnetic iron porphyrins is slow then the observed correspondence in relaxation times between S=0 and S=2 iron(II) porphyrins may not necessarily indicate that the relaxation pathways are the same. 

Prussian Blue. Reaction of [Fe(CN)6]4 with an excess of aqueous iron(III) produces the finely divided, intensely blue precipitate Prussian Blue [14038-43-8] (tetrairon(III) tris(hexakiscyanoferrate)), Fe4fFe(CN)6]. Prussian Blue is identical to Turnbull s Blue, the name which originally was given to the material produced by reaction of [Fe(CN)6]3 with excess aqueous iron(II). The solid contains or has absorbed on its surface a laige and variable number of water molecules, potassium ions (if present in the reaction), and iron(III) oxide. The iron(II) centers are low spin and diamagnetic iron(III) centers are high spin. Variations of composition and properties result from variations in reaction conditions. Rapid precipitation in the presence of potassium ion affords a colloidal suspension of Prussian Blue [25869-98-1] which has the approximate composition IvFe[Fe(CN) J. Prussian Blue compounds are used as pigments in inks and paints and its formation on sensitized paper is utilized in the production of blueprints. 

The monoanionic nitrosyl complexes (14-18) [Fe(NO) —S2 2] are probably diamagnetic iron(II) complexes with structure V, the considerably lower chemical isomer shift being produced by the back donation of electrons to the nitrosyl group. The [Fe(NO) —S2 2] complexes (19-23) feature an additional electron which is beheved to be in a n NO orbital. This decreases the d -p back donation by the iron atom to these orbitals, effectively increases the 3d-electron density and increases the chemical isomer shift. 

Schiff base complex Co(Bzacen)py02 9 Bzacen = JV,JV -ethylenebis(benzoylacetoneiminato) and the diamagnetic iron picket-fence porphyrin Fe TpivPP)(Meim)02 (10) where the iron atom is surrounded by a cage which prevents the dioxygen species from reacting with another iron atom (TpivPP= meso-tetrakis(a,a,a,a-o-pivalamidophenyl)porphyrinato, Meim = 1-methylimid-azole). ... 

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