Cocondensation of the high-temp. mol. AlBr with a PhMe/THF mixt. gave a colorless, brittle compd. of the compn. Al5Br7.5THF which from x-ray structural anal. can be formulated as [Al(AlBr.2THF)2(AlBr2.THF)2]+[Al(AlBr2.THF)4]- (I). I triclinic, space group , Z = P.hivin.1, R1 = 0.0546, wR2 = 0.1366. The central Al in both the cation and anion is tetrahedrally surrounded by 4 Al atoms. The mol. structure of I was calcd. by DFT methods. I decomps. on warming to 100 Deg. The mechanism for the formation of I is discussed. Al2I4.2THF (II) was obtained from AlI in a PhMe/THF mixt. II is orthorhombic, space group Pca21, Z = 4, R1 = 0.0428, wR2 = 0.1089. II displays the typical D.X2Al-AlX2.D structure. [on SciFinder (R)]