Location and acidity of Brønsted acid sites in isomorphously substituted LTL zeolite: A periodic density functional study

摘要: Abstract Isomorphously substituted LTL zeolite ([M]-LTL) was studied by the periodic density functional theory. Two different tetrahedral Si atoms of (T1 and T2) were replaced a series trivalent (M = Al, B Ga). The relative energies structural configurations show that T1 site located at 12-membered rings is most favorable for M substitution. For [M]-LTL where substituted, Bronsted acid sites (O3, O4, O6) intensively calculating deprotonation energy, O–H vibrational frequency, charge bridging oxygen, adsorption energy probe molecules (ethylene, acetonitrile pyridine) with [B]-, [Ga]-, [Al]-LTL models. A direct correlation between those four parameters observed trend acidity isomorphously systems predicted as: [B]-LTL