The thermal properties of four heteropoly complexes alpha-K3H3[SiW11Ni
(H2O)O-39]. 11.5H(2)O (I), alpha-K3H2[SiW11Fe(H2O)O-39]. 9H(2)O (II),
alpha-[(C4H9)(4)N]H-3.5(1.5)[SiW11Fe(H2O)O-39]. 4.5H(2)O (III) and alp
ha-[(C4H9)(4)N]H-3.5(2.5)[SiW11Cu(H2O)O-39]. 6H(2)O (IV) were studied
by means of TG, DTA and DSC. The activation energy and reaction order
of the thermal decomposition reaction of these complexes have been cal
culated.