The diethyl ether adducts Et2O . MI3 (M = Ga or In) have been converted by reaction with the macrocyclic ether 1.4,7,10,13,16-hexaoxacyclooctadecane (18-crown-6) into complex ionic products [MI2(18-crown-6)][MI4]. Raman and IR spectra yielded the assignments: for [GaI2](+), nu(1) 161; nu(2) 60; nu(3) 313 cm(-1); for [InI2](+), nu(1) 150, nu(2) 46, nu(3) 258 cm(-1). X-Ray analysis of the indium compound as colourless monoclinic crystals revealed a weakly complexed [InI2](+) cation with In-I 2.617(1) and 2.619(1) Angstrom and an I-In-I angle of 170.14(4)degrees threaded through the cavity of the crown ether, and a distorted tetrahedral [InI4](-) anion with the average In-I bond length of 2.708(2) Angstrom.