Topotactical redox reactions

Bruce PG, Irvine ITS (2001) Insertion Compounds. In Encyclopedia of Materials Science and Technology, Elsevier Science Ltd Oxford ISBN 0-08-0431526, pp. 4115-4121 SchoUhom R (1980) Reversible topotactic redox reactions of solids by electron/ion transfer. Angew Chem Int Ed Engl 19 983-1003... 

The transition metal oxyhalides occur with four main structure types (FeOCl, AlOCl, SmSI, and PbFCl) but only the FeOCl structure undergoes topotactic redox reactions. A layer of the orthorhombic FeOCl structure is shown in Figure 21. The structure is characterized by double sheets of distorted octahedra that share edges. Each iron atom is coordinated to four oxide anions and two chloride ions, with the two chloride ions in cis octahedral positions on the outside of the layer. The arrangement of octahedra within a layer is similar to that found in y-FeOOH and y-AlOOH. 

Schollhom R, Kuhhnann R, Besenhard JO (1976) Topotactic redox reactions and ion exchange of layered M0O3 bronzes. Mater Res Bull 11 83-90... 

Figure 8.8 Formation of hydrated phases by topotactic redox intercalation reaction in aqueous electrolytes (a) host lattice MX2 (b) monolayer hydrate (H20)j,[MX2] and (c) bilayer hydrate. (After Schollhorn, 1980).

Nemudry, A., Rudolf, P., and Schollhom, R. (1996) Topotactic electrochemical redox reactions of the defect perovskite SrCo02.s+. Chem. Mater., 8, 2232. 

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