Vaporization of CdIn/sub 2/Se/sub 4/(s)

The vaporization behavior and vapor pressures over samples initially CdIn/sub 2/Se/sub 4/(s) were determined by simultaneous Knudsen effusion and torsion effusion methods. Isothermal thermogravimetry with the Knudsen balance and torsion pendulum as probes were conducted. CdIn/sub 2/Se/sub 4/(s) vaporized incongruently in the range 961-1100 K, and produced Cd(g), Se/sub 2/(g), and CdIn/sub 6/Se/sub 10/(s); the third law ΔH0(298 K) was 232.4 +- 0.2 kJ/mol of CdIn/sub 2/Se/sub 4/. CdIn/sub 6/Se/sub 10/(s) vaporized incongruently in the above range and produced Cd(g), Se/sub 2/(g), and InSe/sub 3/(s); the third law ΔH0(298 K) was 350.9 +- 0.2 kJ/mol of CdIn/sub 6/Se/sub 10/. Vaporization studies with the residual In/sub 2/Se/sub 3/(s) confirmed the conclusions from a recent study of In/sub 2/Se/sub 3/ in which it was shown that In/sub 2/Se/sub 3/(s) vaporizes incongruently. An anomalous isothermal increase in rate of mass loss during thermogravimetry was explained by a change in the nature of the effusing vapor