Raman and infrared spectroscopy of the AlCl3–SOCl2 system

Abstract

The structural aspects of the AlCl₃–SOCl₂ system have been examined by vibrational spectroscopy. The SOCl₂ molecule exhibits amphoteric character, i.e. it can act simultaneously as a donor through the oxygen atom and as an acceptor through the sulphur atom. The liquid state contains loosely bound, open-chain dimers/oligomers, (Cl₂SO)_n with n 2. The dissolution of Al₂Cl₆ in SOCl₂ occurs dissociatively with the formation of Cl₂SO → AlCl₃ adducts. At higher AlCl₃ concentrations, an increase in solution electrical conductivity is attributed to the reaction: 2Cl₂SO → AlCl₃⇌[Cl₂Al(â†� OSCl₂)₂]⁺+ AlCl^–₄