The isolation and characterisation of strong proton acids derived from aluminium, iron, gallium, and indium trichlorides

Abstract

A series of ether complexes of strong proton acids of the type [(Et₂O)_nH]⁺[MCl₄]^–(M = Al, Fe, Ga, or In) were obtained as oils when diethyl ether solutions of the metal trichlorides were mixed with the equivalent amounts of hydrochloric acid. The acids were characterised by analysis, potentiometric titrations, i.r. spectroscopic measurements, and electrical conductivity measurements in nitromethane. The acid with M = Fe was also characterised by its electronic spectrum and magnetic moment.