The structural and optical properties of LiZnN prepared by potentiostatic electrolysis of a Zn electrode at 0.7 V (Li+/Li) in LiCl-KCl-Li3N were investigated. An X-ray diffraction analysis clarified that the obtained film consisted of a single-phase LiZnN (lattice constant 0.490 nm, crystallite size 60 nm, film thickness 5 mu m for 2 h). Reflectance measurements revealed that LiZnN has a direct bandgap of 1.9 eV at room temperature. Furthermore, a red luminescence has been confirmed by irradiation of 325-nm and 442-nm light at 6-150 K. This luminescence is interpreted to result from electron-hole recombination between conduction and valence bands or shallow levels of defects or impurities, as the luminescence band contains three sub-bands, and all of them correspond to or close to the estimated bandgap energy. (c) 2005 The Electrochemical Society. [DOI: 10.1149/ 1.2135217] All rights reserved.