Abstract (EN):
Salts of the heteropolytungstates [PW11M(H2O)O-39](5-)(,) M=Cu, Co, Mn, with the following complex cations were prepared: [Cu(LL)(2)(H2O)](2+) , [Cu(LL)(3)](2+) , LL=1,10-phenantroline (phen), 2,2 ' -bipyridine (bipy), [Cu(phen)(2)Cl](+), [CO(bipy)(2)(CO3)](+), and [Co(phen)(3)](2+). Compounds with [SiW11M(H2O)O-39](6-), M = Cu, Co, Mn, and the cations [Cu(LL)(2)(H2O)](2+), and [CO(bipy)(2)(CO3)](+) were also prepared. Synthesis was carried out in aqueous or nitromethane solutions. The compounds were characterised by elemental and thermal analysis and spectroscopic techniques. Spectroscopic properties and the thermal stability of the polyanions; in these compounds could thus be compared with those of simpler Salts. BET surface areas were determined. Except for salts of [Cu(bipy)(3)](2+), the compounds decompose on heating at temperature above 200 degreesC, the exact temperature depending on the cation. Some are stable up to 300 degreesC. For salts of the [Cu(LL)(2)(H O-2)](2+) cations, more detailed thermal studies were performed, based on the infra red spectra of the decomposition products obtained at several temperatures.
Idioma:
Inglês
Tipo (Avaliação Docente):
Científica
Nº de páginas:
17