A composition having a polythiol reactant and an alkenyl silane reactant which are combined to form a polysulfide polysilane. In the process, the reactants are combined in a thiol-ene addition process driven by UV radiation. The polysulfide polysilane is then hydrolyzed and may be combined with other hydrolyzed compounds. For coatings, the polysulfide polysilane is hydrolyzed and may optionally be combined with nanoparticles. For bulk materials, the polysulfide polysilane is hydrolyzed, concentrated and heated to form a high refractive index material which can be used to form lenses.