Complex halides of the transition metals. Part XIV. The X-ray photoelectron spectra of mononuclear and dinuclear complex halides of rhenium(III) and rhenium(IV), and of the Re(NCS)62– and Re2(NCS)82– complex anions

Abstract

Rhenium 4f and chlorine 2p electron binding energies have been recorded for a series of complex halides of rhenium in the formal oxidation states +4 and +3. Referencing the rhenium 4f_7//2 level to a standard chlorine 2p value provides a guide to the metal oxidation state and allows a ‘correction’ to be made for small variations in Madelung potential within a series of salts of a particular complex halide (e.g., Re₂Cl₈^2–). Both bridging and terminal rhenium-chlorine atoms have been distinguished in the [Re₂Cl₉]^– and [Re₂Cl₉]^2– anions. Little variation in rhenium 4f binding energies was observed for a series of anions of the type [ReCl₅,L]^–. The rhenium 4f binding energies of the Re(NCS)₆^2– and Re₂(NCS)₈^2– anions are also reported together with the nitrogen 1s and sulphur 2p levels of the pseudohalide ligand molecules.