Inorganic Oxides as Supports for Organometallic Species

R = fert-butyl or phenyl. (Reprinted from Reference [2].) 

Among the several transition alumina phases, y-Al203 is the most important and most studied phase for catalysis [57, 58]. However, even nowadays, several aspects of its structural and surface chemistry are still not well understood, since y-Al203 is a poorly crystalline solid, showing some variation in its structural stoichiometry and a wide range of defects. In the last 50 years, several empirical models for y-AI2O3 surface have been reported, trying to explain the complexity of this surface 

The hydroxyls at the terminal configurations of the surface (types la and lb) are the less acidic and more labile groups, whereas the hydroxyls in the bridged configurations (types 11a, 11b and 111) are sluggish and prone to act as proton donors 

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