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The Raman spectrum of Ge(2)Cl(6) shows close analogies with that of the isoelectronic [Ga(2)Cl(6)](2)(-). A band at 262 cm(-)(1) is assigned as principally a Ge-Ge stretching mode. The compound is very moisture-sensitive and decomposes readily in vacuo to give GeCl(4) as one of the products. A sealed sample stored at room temperature gave colorless cuboidal crystals shown by X-ray crystallography to be Ge(5)Cl(12).GeCl(4). The Ge-Ge distance in the neopentyl-like Ge(5) skeleton is 2.420(6) Å, and the Ge-Cl distance in the Ge(5)Cl(12) moiety is 2.119(5) Å whereas in the case of the GeCl(4) molecule it is 2.082(7) Å. The symmetric stretching frequency of the Ge(5) tetrahedron is assigned to the band at 224 cm(-)(1).

The Raman and infrared spectra of gas phase Re(2)O(7) are reported. The experimental vibrational spectra of molecular Tc(2)O(7) and Re(2)O(7) are compared with calculated spectra. The results of these studies agree with a nonlinear M-O-M bridge for Tc(2)O(7) and Re(2)O(7). For infrared intensity calculations, the point charge approximation is used, while for the Raman calculations a combination of bond and atom polarizabilities is adopted. Pure Re(2)O(7) was prepared from rhenium wire, but attempts to prepare it from rhenium powder and oxygen always led to infrared spectra showing serious contamination from a species containing an -OH linkage. Detailed experiments identified this molecule as HReO(4), a unique transition metal analogue of the perhalic acids, and a partial infrared spectrum of this molecule is reported.