The absorption spectra of SnI₄, SuBr₄, SnCl₄, SnBr₂, C₂I₄, C₂I₂, C₂H₄I₂, CH₂I₂
have been measured in various solvents. It is shown
that results of previous workers for SnI₄ have been
subject to errors due to decomposition of the compound.
This decomposition was prevented in the curves obtained in this work. The decomposition could not be
stopped in the case of SnBr₄ and a hypothesis is put
to explain this difference in the behaviour of SnI₄
The spectra of the iodine compounds are discussed
on the basis pf the theory that in compounds containing several iodine atoms and weak X - I bonds part
of the absorption is due to interaction between the
The effect of change of solvent on the absorption
of the carbon compounds was studied and a tentative
explanation put forward.