RBS STUDIES OF THE INTERCALATION COMPOUND HGXTIS2 - MORPHOLOGY AND STAGING

In order to study the intercalation process of Hg into the layered cry stal TiS2 we performed Rutherford Backscattering (RBS) and channeling experiments on TiS2 and on the intercalation compound HgxTiS2 with var iable Hg uptake. After the intercalation of Hg in TiS2 we observed a c lear Hg-signal in the RES-spectrum, increasing with reaction time and temperature. The variation of the Hg RES-signal depending on the later al position of the analysing beam cannot be explained by vertical reac tion fronts or by a spatially homogenous intercalation process. We con clude from these measurements that the intercalation process proceeds parallel to the TiS2 layers in concave reaction fronts. The empty TiS2 crystal exhibits a good channeling effect (chi(min) approximate to 20 %). Owing to Hg uptake, however, the ion channeling effect in the ''mi sfit compound'' HgxTiS2 vanishes. We attribute this to the incommensur ability of the Hg and TiS2 sublattices as well as to a bending of the crystal induced by the intercalation process. (C) 1998 Elsevier Scienc e B.V.