Influence of Co(III) complexes on formation of polyoxometalate species

U ovom diplomskom radu provedeno je ispitivanje utjecaja četiri različita kompleksa kobalta(III) na sintezu novih polioksometalatnih vrsta. Nadalje, ispitani su utjecaji prisustva karboksilnih (di)kiselina u reakcijskom sustavu te različitih stehiometrijskih omjera polaznih spojeva na ishod sinteze. Reakcije priprave spojeva su provedene pri povišenoj temperaturi uz refluks, hidrotermalno te tekućinom potpomognutim mljevenjem uz starenje potpomognuto parama otapala. Dobiveno je šest novih polioksometalatnih spojeva kojima je određena struktura te nekoliko već poznatih sustava dobivenih alternativnom metodom sinteze. U tri novo dobivena spoja kao anionska vrsta pojavljuje se dekavanadatni anion, kod dva heteropoliokso metalatni anion molibdena i vanadija te jedan koordinacijski polimer vanadija. Spojevi su okarakterizirani primjenom infracrvene spektroskopije, difrakcije rentgenskog zračenja na polikristalnom uzorku te termičkom analizom, dok je molekulska i kristalna struktura određena difrakcijom rentgenskog zračenja na monokristalnom uzorku.In this diploma thesis, a study of the influence of four different cobalt (III) complexes on the synthesis of new polyoxometallate species was carried out. Furthermore, the influence of the presence of carboxylic (di)acids in the reaction system and different stoichiometric ratios of the starting compounds on the synthesis outcome were investigated. Reactions were carried out at elevated temperature under reflux, hydrothermally, and with liquid-assisted milling with vapour-assisted aging. Six new polyoxometallate compounds were obtained, whose crystal structures were determined, and several already known systems by an alternative method of synthesis. Decavanadate anion is present in three of the obtained compounds, a molybdovanadate anion in two of them, and one of them is a polymeric system of vanadium. The compounds were characterized by infrared spectroscopy, X-ray diffraction on a polycrystalline sample, and thermal analysis, while the molecular and crystal structure was determined by X-ray diffraction on a monocrystalline sample