Thermodynamic study of gaseous ternary oxide molecules. The europiumndash;vanadiumndash;oxygen system

摘要

The gaseous ternary oxide molecules EuVO3and EuVO2have been identified by high temperature mass spectrometry in the vapors in equilibrium over a mixture of europium and vanadium oxides in a molybdenum cell. From the study of four allhyphen;gas equilibria, the stability of these molecules has been derived:Ddeg;o,at(EuVO3)=2192.5plusmn;16 kJthinsp;molminus;1,Ddeg;o,at(EuVO2)=1504plusmn;11 kJthinsp;molminus;1. The appearance potentials were measured as: 8.1plusmn;0.5 and 8plusmn;1 eV for EuVO+3and EuVO+2, respectively.