Ab Initio Study of Defect Sites at the Inner Surfaces of Mesoporous Silicas

Ab initio molecular dynamics simulations on 1-nm thick slabs of amorphous silica have been carried out in order to mimic the local properties of mesoporous materials framework. A number of defects have been considered, both with closed and open shell electronic structure, and their spectroscopic properties analyzed and compared with experiments. The “strained siloxane bridge” defect has been studied in detail and its possible radical nature highlighted.