Acidity of Amorphous Silica-Alumina: From Coordination Promotion of Lewis Sites to Proton Transfer
C Chizallet and P Raybaud
Chem. Phys. Chem. 11, 105 (2010)
Local structure resolved: The debated nature of Brønsted acid sites on amorphous silica-alumina is investigated by DFT calculations. Bridging Si-(OH)-Al and pseudo-bridging silanols, in through-space interaction with AlIV or SiIV, are deprotonated by nitrogenated probe molecules, simultaneously forming pentacoordinated species.