Crystalline aluminium hydroxy fluorides—Suitable reference compounds for 19F chemical shift trend analysis of related amorphous solids

Novel Sol–Gel Synthesis of Acidic MgF2−x(OH)x Materials

“…[6] 19 F MAS NMR studies on crystalline AlF x (OH) 3Àx ·H 2 O samples also showed a low-field shift in the fluorine signal with increasing amount of hydroxyl groups. [21] Therefore, with decreasing HF concentration, and hence increasing H 2 O concentration, the amount of hydroxyl groups in the final MgF 2 increases, and this is reflected in the appearance of the low-field shift in the 19 F spectra.…”

Physico-chemical characterization of metal-doped bone chars and their adsorption behavior for water defluoridation

“…On the other hand, bone chars doped with aluminum salts have similar crystalline structures and XRD profiles than that obtained for raw BC. The surface modification using these aluminum salts caused a slight deterioration of the diffraction peaks that could be attributed to the incorporation of Al 3+ ions on the bone char surface and König et al [64]. FTIR spectra of raw and metal-doped bone chars are reported in Fig.…”

Influence of milling, sonication and fluoride doping of pseudoboehmites on their phase transformation behaviour to corundum

“…The signal at 6 ppm stands for six-fold oxygen-coordinated Al in AlOOH 31 while the 27 Al signal at −16 ppm and the 19 F signal at −173 ppm are typical for ␣-AlF 3 . [33][34][35] After thermal treatment at 700 • C, the 27 Al spectrum of MD (Fig. 3) shows the typical spectral pattern of ␥-Al 2 O 3 31,32,36,37 with two peaks at 63 and 10 ppm.…”