The cubic network of 30 angstrom diameter supercages in the novel gallophosphate molecular sieve cloverite receives attention in this work because of its potential as a host in innovative host-guest nanochemistry aimed at advanced materials applications. A multiprong analytical approach (PXRD, TGA/DSC/TMA/MS, H-1, C-13, P-31, Ga-71, Xe-129 NMR, UV-Vis, FT-IR, Raman, physical adsorption) is employed to begin the exploration of the thermal and chemical properties of cloverite, as-synthesized with the quinuclidine template and following various post-synthesis treatments. The freezing out of guest motions (template/water) and/or a change in the space group of as-synthesized cloverite occurs around -57-degrees-C. Removal of extraframework H2O occurs in two barely resolved stages at 90-degrees-C and 110-degrees-C. At this stage the quinuclidine template exists predominantly in the protonated form. The dehydration event is reversible and has very little effect on the integrity of the cloverite framework. Acid-base titrations of dehydrated cloverite with anhydrous NH3 and HCl at room temperature reveal the essentially neutral nature of both the P(OH) and Ga(OH) hydroxyl groups of the interrupted framework of cloverite. This is to be contrasted with defect hydroxides in cloverite which behave as Bronsted acid sites. However, all P(OH) and Ga(OH) groups can be selectively deuterated with D2 at 240-degrees-C and D2O at room temperature, leaving the hydrogens on the quinuclidinium template effectively untouched. Xe gas can access the larger, but not the smaller, channel of cloverite, both as-synthesized and after dehydration at 150-degrees-C. Three thermal events occur around 350-degrees-C, 450-degrees-C, and 550-degrees-C in which the occluded template (25%, 70%, 100%) and framework hydroxyls (40%, 90%, 100%) arc systematically depleted from cloverite, simultaneously with the evolution of quinuclidine cracking products, framework HF, and H2O. At each of these stages, Xe gas can only gain access to the supercages, being excluded from the LTA/RPA channel system of cloverite. The proton on the quinuclidinium housed in the interrupted framework of cloverite appears to play a key role in the production of dehydroxylated-dehydrofluorinated and/or partially fragmented double four-rings, through the thermally induced loss of framework HF and H2O over this temperature range. However, up until about 450-500-degrees-C, the disruption of double four-rings appears to be localized and short-range in nature. It does not appear to significantly reduce the crystallinity of cloverite at the unit cell level or the framework microporosity of the material, the latter with respect to O2 and n-hexane adsorption. This process continues up to 800-degrees-C, with the unit cell maintained essentially intact, at which point one observes catastrophic breakdown of the cloverite structure. The collapsed material at this stage is X-ray amorphous, but around 850-degrees-C it recrystallizes predominantly into the dense phase tridymite form of GaPO4. Between 850 and 1050-degrees-C the evolution of CO is observed, which is considered to arise from a carbothermal reduction of the gallophosphate by residual carbon. A transformation of GaPO4-tridymite into predominantly GaPO4-cristobalite occurs around 1000-degrees-C. A sintering transition begins around 1090-degrees-C. Clearly the unit cell of cloverite remains essentially intact up until around 800-degrees-C, although some short range disorder is introduced into the system up to this stage, most likely originating from the random production of disrupted double four-rings.
