Salts of alkali metal anions (alkalides) or trapped electrons (electrides) will be synthesized as homogeneous thin films by vapor deposition and as microcrystalline films by solvent evaporation. The optical properties will be studied by transmission spectra, reflectance spectra (from single crystals) and fluorescence spectra. Electron energy loss spectra in a field emission scanning transmission electron microscope will be measured. The conductivity and photoconductivity of thin films will be determined in the vapor deposition apparatus. Photoelectron emission and thermionic electron emission will be studied by using both specialized equipment and the vapor deposition system. The study of the optical and electronic properties of alkalides, electrides and mixed systems should permit determination of the nature of electron.electron interactions in a crystalline solid with weakly trapped electrons, the factors which lead to electron spin pairing, and the nature of the metal.non metal transition in a crystalline analog of metal.ammonia solutions. The weak binding of electrons in electrides leads to thermionic emission and photoelectron emission in the near infrared. Extension of these studies might lead to the development of an infrared photoelectron emitter.