Monodisperse particles having: a single pure crystalline phase of a rare earth-containing lattice, a uniform three-dimensional size, and a uniform polyhedral morphology are disclosed. Due to their uniform size and shape, the monodisperse particles self assemble into superlattices. The particles may be luminescent particles such as down-converting phosphor particles and up-converting phosphors. The monodisperse particles of the invention have a rare earth-containing lattice which in one embodiment may be an yttrium-containing lattice or in another may be a lanthanide-containing lattice. The monodisperse particles may have different optical properties based on their composition, their size, and/or their morphology (or shape). Also disclosed is a combination of at least two types of monodisperse particles, where each type is a plurality of monodisperse particles having a single pure crystalline phase of a rare earth-containing lattice, a uniform three-dimensional size, and a uniform polyhedral morphology; and where the types of monodisperse particles differ from one another by composition, by size, or by morphology. In a preferred embodiment, the types of monodisperse particles have the same composition but different morphologies. Methods of making and methods of using the monodisperse particles are disclosed.
STATEMENT OF U.S. GOVERNMENT SUPPORT
 This invention was made with U.S. government support under STIR grant R41EB008959 awarded by the National Institute of Health, under grant DMR-0505048 awarded by the National Science Foundation, under grant DMR 05-20020 awarded by the National Science Foundation, under grant NNX08AO0G awarded by the National Aeronautical and Space Agency, under grant W911NF-08-1-0364 awarded by the Army Research Office, under grant DMS-0935165 awarded by the National Science Foundation, and under grant DE-SC0002158 awarded by the Department of Energy. The U.S. government has certain rights in this invention.