Thermal decomposition of the [[Pt[.sub.4]].sup.2+] complex in NaX zeolite: effect of cesium as the compensation cation

The effect of the calcination procedure on the decomposition of the [[Pt[(N[H.sub.3]).sub.4]].sup.2+] complex in a cesium-containing NaX zeolite was studied by thermal decomposition accompanied by mass spectrometry and diffuse reflectance spectroscopy, as well as electron paramagnetic resonance and infrared spectroscopy. The decomposition of the complex took place in two steps. Under oxygen, the [[Pt[(N[H.sub.3]).sub.4]].sup.2+] complex was first converted into the [[Pt[(N[H.sub.3]).sub.4]].sup.2+] complex in the first step, with predominant nitrogen release. In the second step, corresponding to the decomposition of the remaining two amine ligands, NO was also formed and adsorbed. Oxygen paramagnetic species were also observed. Under He, the decomposition also occurred in two steps with [H.sub.2] release.