Insights into the Geometry, Stability and Vibrational Properties of OH Groups on γ-Al2O3, TiO2-Anatase and MgO from DFT Calculations

The properties of hydroxyl groups on γ-Al2O3, TiO2-anatase and MgO are rationalized by Density Functional Theory calculations. Oxide ionicity is found to be determinant in the water/oxide interaction strength when dissociation of H2O occurs, and in the bridging ability of monocoordinated surface OH groups. For a hydroxyl, being the hydrogen bond donor, acceptor or having an isolated nature is found to be the most important parameter governing the O–H stretching frequency.