AbstractThe Raman spectra of solid and liquid gallium trichloride are communicated. From the number of frequency shifts found and from the frequency values it is probable that gallium trichloride is present as double molecules Ga2Cl6in the solid and in the liquid. The structure of these double molecules is probably that of the ethylenic (bridge) model as was formerly concluded for Al2Cl6etc., although the absence of polarization measurements makes this conclusion less conclusive. The result is in agreement with the crystal structure determination of Ga2Cl6as given in the Thesis ofRenes. A comparison is made between experimental and calculated frequency values for the “ethane” and the “ethylenic”