Abstract: Novel compositions and methods of using those compositions to form high refractive index coatings are provided. The compositions preferably comprise both a reactive solvent and a high refractive index compound. Preferred reactive solvents include aromatic resins that are functionalized with one or more reactive groups (e.g., epoxides, vinyl ethers, oxetane), while preferred high refractive index compounds include aromatic epoxides, vinyl ethers, oxetanes, phenols, and thiols. An acid or crosslinking catalyst is preferably also included. The inventive compositions are stable under ambient conditions and can be applied to a substrate to form a layer and cured via light and/or heat application. The cured layers have high refractive indices and light transmissions.