Thermodynamics of the Zr-ZrO2 System : The Dissociation Energies of ZrO and ZrO2

Abstract
A mass spectrometric analysis of vapors effusing from a Knudsen cell containing either solid ZrO2 or a mixture of Zr and ZrO2 powders has been employed to determine the vapor pressures, and hence the heats of sublimation of these species. Combined with published thermodynamic data, these results yield 7.8±0.2 ev and 14.5±0.2 ev for the dissociation energies of ZrO and ZrO2, respectively. Previous work is shown to be in error due to the volatility of TaO.