Vapor Composition over Solid Indium Trichloride and in Indium Chloride Unsaturated Vapor

The dependence of indium trichloride saturated and unsaturated vapor pressure on temperature was studied in the range of 630-950 K by static methods using a quartz membrane zero-manometer and taking into account the volume of its working chamber and substance mass. The thermodynamic data on the process of dissociation of dimeric molecules and sublimation of monomer and dimer from solid indium trichloride were calculated: Delta H-subl(0) InCl3(g)(298) = 155.3 +/- 6.2 kJ.mol(-1); Delta S-subl(0) InCl3(g)(298) = 199.5 +/- 7.9 J.mol(-1)K(-1); Delta H-subl(0) In2Cl6(g)(298) = 159.3 +/- 6.2 kJ.mol(-1); Delta S-subl(0) In2Cl6(g)(298) = 207.1 +/- 3.8 J.mol(-1).K-1; Delta H-dis(0) In2Cl6(g)(298) = 152.6 +/- 5.5 kJ.mol(-1) and Delta S-dis(0) In2Cl6(g)(298) = 171.6 +/- 5.2 J.mol(-1).K-1. The saturated vapor over solid indium trichloride consists mainly of a mixture of monomeric and dimeric molecules (InCl3 and In2Cl6), and the content of the latter is slightly growing with increasing temperature.