Structure D 2000Synthesis, Physicochemical Characterization and Crystallographic Twinning of Li 2 ZnSnS 4 . -Single crystals of the title compound are prepared by solid state reaction of a stoichiometric mixture of Li2S, Zn, Sn, and S (graphite crucible, 825°C, 72 h) and characterized by XRD, SEM, EDS, DTA, diffuse reflectance UV/VIS/NIR spectroscopy, and second harmonic generation measurements. Li2ZnSnS4 crystallizes in the monoclinic space group Pn with Z = 2. All ions possess tetrahedral environments, with each sulfide anion being surrounded by one zinc, one tin(IV), and two lithium cations. Even though Li2ZnSnS4 is noncentrosymmetric, it does not exhibit any second harmonic generation response. The title compound is a new diamond-like semiconductor, which is of interest as a host structure for the creation of potentially interesting electronic, magnetic, and photovoltaic materials. -(LEKSE, J. W.; LEVERETT, B. M.; LAKE, C. H.; AITKEN*, J. A.; J. Solid State Chem. 181 (2008) 12, 3217-3222; Dep. Chem. Biochem., Duquesne Univ., Pittsburgh, PA 15282, USA; Eng.) -W. Pewestorf 11-007