Liquid GaCl3 and GaCl3–NaCl mixtures oxidize bismuth metal to subvalent bismuth cations and such species are also formed in Bi–GaCl3–benzene and Bi–BiCl3–GaCl3–benzene solutions at room temperature. In Bi–GaCl3 and Bi–GaCl3–NaCl melts, 71Ga NMR, UV–VIS and Raman spectroscopy identify Ga+, halogallate(III) ions, Bi+ and the cluster Bi53+ as reaction products and Bi5(GaCl4)3 can be crystallized from Bi–GaCl3 melts. Furthermore, Raman spectra and powder diffraction data or quenched samples of the Bi–GaCl3 system give evidence for the formation of more reduced bismuth clusters at high formal bismuth concentrations. In benzene solution, Bi+ and Bi53+ are formed; no evidence for other, more reduced, species are found. In order to interpret the 71Ga NMR and Raman spectra of the Bi–GaCl3–benzene system properly, a detailed investigation of the Ga–GaCl3–benzene system was undertaken. The spectroscopic data from this system support the view that the chlorogallate (III) ion accompanying the subvalent ions Ga+ and Bi53+ in Bi–GaCl3–benzene solution is Ga3Cl10–. Liquid X-ray scattering (LXS) measurements confirm the speciation of the Bi–GaCl3–benzene system and show that the structure of Bi53+ is virtually identical with that in the solid state. Interactions between Bi53+ and the aromatic solvent are evident from a Raman band at 986 cm–1 next to the most intense band of C6H6 at 992 cm–1. However, LXS and 13C NMR are inconclusive as to the nature of this interaction. Upon dilution of Bi–GaCl3–benzene solutions by n-heptane, a new modification of Bi5(GaCl4)3 precipitates, as shown by powder diffraction. Rietveld analysis shows this modification to possess cubic symmetry (Fm3c, a= 17.114 A) and a high degree of structural disorder.
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