Robert Schöllhorn* and Wolfgang Schramm Anorganisch-Chemisches Institut der Universität Münster, Gievenbecker Weg 9, D-4400 Münster Z. Naturforsch. 84b, 697-699 (1979); received February 19, 1979 Topotactic Reactions, Intercalation Compounds, Niobium Chalcogenides, Ionic Conductivity, Superconductivity Cathodic reduction of Nb3S4 and Nb3Se4 electrodes in electrolytes containing cations of appro...