Ferroelectric single crystals of triglicine sulphate (TGS) doped with lysine (TGSL10) were grown from a water solution, below Curie point, with use of static method, by evaporation of the solvent. Morphology changes were observed in new grown single crystals, in comparison to pure TGS. Parameters of the crystal lattice were determined with use of powder X-ray diffraction method and compared with parameters of pure TGS. Temperature characteristics of spontaneous polarization Ps and coercive field Ec were measured as well as observations of domain structure of new material.© (2003) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.