trihalide have been shown to be mixtures of metallic gallium with, respectively, Ga2Br3 and Ga2I3. GaCl and GaBr GaCl and GaBr have been produced in the gas form from the reaction of HX and molten gallium using a special reactor. They have been isolated by quenching the high temperature gas at 77 K. GaCl is reported as a red solid that disproportionates above 0 °C. Both GaCl and GaBr produced in this way can be stabilised in suitable solvents. The metastable solutions formed in this way have been used as precursors to numerous gallium cluster compounds. In the HVPE production of GaN, GaCl is produced by passing HCl gas over molten gallium which is then reacted with NH3 gas. GaI GaI is produced as a reactive green powder, which has been hailed as a "versatile reagent for the synthetic chemist". The chemical structure of the reagent termed ‘GaI’ produced from reacting gallium metal with iodine in toluene using ultrasound has only recently been investigated using 69/71Ga solid-state NMR and a tentative structure assigned which includes gallium metal atoms, [Ga0]2[Ga]+[GaI4]−. Anionic halide complexes Salts containing GaCl4−, GaBr4− and GaI4− are all known. Gallium is very different from indium in that it is only known to form 6 coordinate complexes with the fluoride ion. This can be rationalised by the smaller size of gallium (ionic radii of Ga(III) 62 pm, In(III) 80 pm). Salts containing the Ga2Cl62− anion, where gallium has an oxidation state of +2, are known. General references WebElements Footnotes Gallium compounds Metal halides Mixed_valence_compounds