Much of our current understanding of catalytic activity is derived from materials with well-defined structures, either molecular (i.e., homogeneous catalysts) or extended, ordered solids (i.e., heterogenous catalysts and surface science), and active sites in real catalysts are often assumed to closely resemble structures found in such ordered materials, at least locally. Yet many real catalysts involve amorphous materials and are much more active than their well -ordered counterparts would suggest. This implies that at least some active sites in amorphous materials are intrinsically different. One of these important and versatile amorphous materials is silica. The materials properties are based in many cases on the way molecules interact with the silica surface. Since several years we investigate silica and its role as support of transition metal oxide catalysts, but also the in- teraction with bio-organic systems, and this at different levels: from the phenomenological description of the interaction at the interface substrate -adsorbate (adsorption and self -assembling of biomolecules) to technologic applications (catalysis, ionic liquids), pharmaceutical (controlled delivery of drug molecules) and their plausible role in different scenarios in the origin of life. For this, we use the tools of quantum chemistry combined with experimental back up with the aim to improve the understanding of the complex chemical behavior of these silica based materials.