Ab initio cluster quantum chemical calculations at the Hartree-Fock (HF) level have been performed for interactions of one and two NO molecules with highly dispersed titanium oxide species incorporated into silicalite (Ti-silicalite) and zeolite (Ti-zeolite) cavities. To find the similarities and differences in the adsorption mechanism, additional calculations have also been carried out on the adsorption of these and other small molecules on pure silica, alumina-silica, and titania, It was found that the NO molecule weakly adsorbs on the Ti-silicalite and Ti-zeolite while it strongly adsorbs on the titania surface. Based on the results of these calculations, different channels of NO decomposition on the Ti-silicalite or Ti-zeolite and on pure titania are discussed.