| Abstract
| - Joint IR and computational results allow a detailed characterization of the surface properties of a mesoporousbenzene−silica hybrid material with crystal-like wall structure. After outgassing at 450 °C, hydroxyl speciesmainly consist of noninteracting silanols, with both O−H and Si−O stretching modes at lower frequenciesthan those of SiOH in silica. Interaction with several probe molecules, followed both by experiment andcalculus, shows that the aryl group in the coordination sphere of Si imparts a lesser acidity with respect to theisolated silanol in silica. In contrast, adsorption isotherms indicate that the interaction with acetone is strongerwith benzene−silica than with silica: this is interpreted in terms of secondary interactions taking place betweenthe slightly acidic CH in acetone and the electronic cloud in benzene-like rings. This suggests that both theinorganic component and the organic one play a role in dictating the surface behavior.
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