  Zeolites, microporous aluminosilicates, are amongst the most widely used
catalysts in the petrochemical industry. Zeolite catalytic functionality is
coupled to the distribution of tetrahedral alumina (AlO4-) and associated
counter-cations throughout the aluminosilicate framework, yet little is
definitively known about the factors that govern framework aluminium
arrangement. It is generally accepted that all zeolites obey Lowensteins rule
of aluminium avoidance and that Al-O-Al linkages are forbidden. Here, we
describe the unprecedented screening of aluminium distribution in catalytically
active zeolite SSZ-13 in both its protonated and sodium containing forms,
H-SSZ-13 and Na-SSZ-13, using density functional theory. We predict violations
of Lowensteins rule in high and low silica H-SSZ-13 and other protonated
frameworks considered in this investigation, H-LTA, H-RHO and H-ABW. The
synthetic realisation of these zeolites could spur the development of new
catalytic routes and materials, and the optimisation of existing zeolite
catalysts.
