The F-Al RDFs of AlPO4-AST zeotypes, shown in Figure , exhibit very different features than those calculated for SiO2-and GeO2-AST: Rather than having one broad maximum, there are two maxima, a sharp one centred at ~1.9 Å, and a considerably broader one centred at ~2. At 573 K, the mobility is enhanced considerably, but there are still two distinct maxima in the F-Al RDFs. This indicates that the fluoride anions remain bonded to Al atoms for the largest part of the simulation time, but move between different bonding partners on the picosecond timescale.