Structures and properties of anionic clay minerals 

 -  Hyperfine Interactions, 117(1-4), p.131-157, 1998 .
<br/><br/> The Mössbauer spectra of pyroaurite-sjögrenite-type compounds (PTC)(layered anion exchangers)are discussed with reference to the crystal structure, cation order, and crystallite morphology. It is shown that cation-ordered layers are produced in the synthesis of carbonate and sulphate types of green rust. In contrast, synthetic and natural pyroaurite only occurs as disordered types. The redox chemistry of Fe(III)within the metal hydroxide layer is illustrated with examples of electrochemical oxidation and reversible reduction by boiling glycerol. The chemistry of iron in the interlayer is exemplified by the intercalation of Fe-cyanide complexes in hydrotalcite. This reaction may be used as a probe for the charge distribution in the interlayer. 
<br/><br/><label>Subjects--Topical Terms: </label><br/>ISOMER SHIFT<br/>QUADRUPOLE SPLITTING<br/>HYDROTALCITE<br/>CENTER SHIFT<br/>GREEN RUST