MULTIVALENT CATION INTERCALATION

Magnesium and zinc have been intercalated into both cubic and layered TiS2, also zinc has been intercalated into the layered compound WO2Cl2. Intercalation has been carried out via chemical routes involving the reaction of the organometallic compounds di-n-butylmagnesium [(C4H9)2Mg], Mg-2,6-di-t-butylphenoxide [Mg-(O-2,6-Bu2tC6H3)2] and di-ethylzinc [(C2H5)2Zn] with the hosts. In the case of magnesium insertion into cubic titanium disulphide, MgxTiS2-C, a continuous range of solid solution, 0 < x < 0.25, is obtained, Rietveld refinements indicates that the Mg2+ ions enter octahedral sites in the TiS2-C structure. Magnesium intercalation into layered TiS2, TiS2-L, results in a mixture of pure TiS2-L and a magnesium rich phase which retains the layered structure of the pure compound but with an expanded unit cell. Zn0.1 TiS2-L and Zn0.1 TiS2-C represents the maximum zinc content which may be obtained using (C2H5)2Zn. Finally, Rietveld refinement indicates that the Zn2+ ions in Zn0.4WO2Cl2 occupy tetrahedral sites between Van der Waals bonded Cl layers of the WO2Cl2 structure.