A series of layered magnesium organosilicate nanocomposites that contain covalently linked organic functionalities have been prepared by a one-step, direct synthesis procedure. The in situ reactivity of organic moieties (e.g., phenyl, thiol) within the layered inorganic-organic nanocomposites, as well as the potential use of thiol-containing materials as host matrixes for the organized deposition of gold nanoparticles, are described.