The distinction of gallium(I) tetrachloroaluminate, Ga[AlCl4], from gallium dichloride

Abstract Ga[AlCl 4 ] is obtained as single crystals via the reduction of gallium trichloride with aluminum and slow cooling of the melt. It crystallizes in the monoclinic system, space group p2 1 /n, with a = 716.4(1), b = 1017.9(2), c = 926.7(1) pm, β = 93.21(1)°. Unlike in gallium dichloride, Ga[GaCl 4 ]], where Ga + has a dodecahedral, eight‐coordinate surrounding, a 6 + 2 + 1 coordination is adopted in Ga[AlCl 4 ] that is similarly observed not only in Ga 2 [Ga 2 Br 6 ] and in tin (II) and lead (II) chalcogenides but also in (the almost isotypic) K[AlCl 4 ].