Luminescent inorganic networks

Silica-based inorganic networks combined with organic rare earth complexes should lead to a new class of luminescent materials, adding the chemical st ability of silica to the strong W absorption of organic ligands and the emi ssive properties of rare earth ions. This concept is demonstrated by the pr eparation of silica xerogels containing benzoic acid in its network and sub sequent react-ion (ion exchange) of these gels with terbium chloride soluti on. The product yields green luminescence similar to the one of solid terbi um benzoate. Alternatively, complete rare earth complexes (example: europiu m thenoyltrifluoracetonate) may be immobilized in silica xerogels, yielding luminescent hybrid materials.