(1) In Klemm and Dierks' method, weighed amounts of the trihalides
and the stoichiometric quantity of metallic In are thoroughly fused
in an evacuated glass vessel to ensure complete conversion to the
corresponding dihalides. The products are purified by vacuum
distillation; in the case of Inl3 the apparatus is sealed off after
evacuation to prevent changes in product composition due to loss
of iodine.
2 InBr3 + In = 3 InBr2
