MECHANISM OF THERMAL-DECOMPOSITION OF PALLADIUM BETA-DIKETONATES VAPOR ON HOT SURFACE

The processes of thermal decomposition of palladium(II) beta-diketonat e complexes were investigated by a high-temperature mass spectrometric method with the use of a high-temperature molecular beam source. It w as established that decomposition of the palladium complexes in gas ph ase processes proceeds by a radical mechanism and depends on temperatu re. For an additional proof of the existence of the radical particles the spin trap method was applied with a mass spectrometric identificat ion of adducts. The following order of thermal stability of the comple xes in gas phase was established: Pd(hfac)(2) > Pd(tfac)(2) > Pd(dpm)( 2) > Pd(acac)(2). This order is reverse to the thermal stability in a solid state. The thermal decomposition of Pd(aa)(2) and Pd(hfa)(2) com plexes in deuterium showed that the deuterium presence strongly accele rates the decomposition processes.