The processes of thermal decomposition of aluminium(II1) and scandium(II1) acetylacetonates (Al(aa)3 and Sc(aa)-,)were investigated in the 160-650°C temperature range using a high-temperature molecular beam source with mass spectrometric sampling of the gas phase composition directly at the outlet from the reaction zone. A scheme of thermal decomposition of aluminium(II1) and scandium(II1) acetylacetonates vapour is suggested. It is established that the common mechanism of thermolysis of these complexes is due to the commonness of electronic structure of ions Mg 2f, A I '+, Sc " and Hf 4+. According to the scheme, the process proceeds along three parallel routes, one of them being possible only for complexes possessing more than two Iigands; in this case the gaseous products resulting from cyclic dimerization of ligand fragments are formed. The influence of oxygen and hydrogen on the composit~on of the gaseous products and the mechanism of ther~~iolysis of the complexes vapour are also established. From temperature curves, the effective values of kinet~c parameters in Arrhenius equation are calculated for the first order reaction.

The processes of thermal destruction of copper(II) bis(dipivaloylmethanate) (Cu(dpm)2) in the temperature range 150~176were studied by using a two-temperature variant of a double chamber Knudsen cell, with mass spectrometric recording of the gas-phase composition. The temperature range of stability of the vapour of the complex in vacuum was determined, as were those of its mixtures with oxygen in different proportions. The temperature dependence of the rate constant of the thermolysis of (Cu(dpm)2) vapour was obtained. The thermal stability of Hdpm vapour and the influence of oxygen on the thermolysis of the ligand were studied.

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By means of a tensimetric flow method and a static method with a silica-membrane zero gauge, the dependence of vapour pressure on temperature was obtained for tds(2,4-pentanedionato)ruthenium(lll), Ru(aa)3, and tris(1,1,l-trifluoropentane-2,4-dionato)ruthenium(IlI), Ru(tfa)3. The thermodynamic characteristics of vaporization and sublimation of these complexes were determined. The processes of thermal decomposition of the vapour of the compounds in vacuum, hydrogen and oxygen were investigated by using mass spectrometry in the temperature range 170-550~ for Ru(aa)3 and 150--620~ for Ru(tfa)3. The threshold temperatures of the stability of the vapour of the complexes and the rate constants of the thermolysis processes were determined. The main gaseous products of the thermal decomposition and the dependences of their composition on the presence of hydrogen and oxygen were established.

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