Sublimation thermodynamics of Al, Cr, Y and Zr acetylacetonates

Evaporation of Al(AA)3, Cr(AA)3, Y(AA)3, Zr(AA)4 acetylacetonates is investigated by the mass-spectroscopy method. Monomer molecules are registered in mass spectra of all compounds, and small dimer impurity - in Zr(AA)4 mass spectrum. Y(AA)3 evaporation is accompanied by two parallel processes: sublimation and thermal decomposition , where yttrium oxide and metal are nonvolatile products. Partial pressures and enthalpies of sublimation are 5.87x10-1 Pa at 389 K for Y(AA)3 and 139.3 ± 5.0 kJ/mol, and at 403 K - 9.20x10-1 Pa for Zr(AA) (8.00x10-4 Pa for dimer molecules) and 150.2 ± 5.4 kJ/mol respectively