Optical properties of sol–gel glasses doped with organic molecules

Abstract
The sol–gel process enables on to prepare oxide glasses at room temperature with little or no heating. By using this method, it is possible to encapsulate a wide variety of organic and organometallic molecules in the inorganic matrix. Studies of this new type of organic/inorganic composite have evolved towards two different objectives: the use of luminescent molecules as probes of the sol–gel process and the deliberate doping of organics to produce materials with specific optical properties. This review emphasizes the ability of encapsulated luminescent molecules to provide unique insights regarding local chemistry and structure during the sol–gel–xerogel transition. The second part of this review gives several examples of how organic-doped sol–gel materials are emerging as an important means of producing photonic materials.