A series of lithium niobate LiNbO3 (LN) single crystals doped by rare-earth elements (Tm, Er, Dy, Tb, Gd, Pr) were grown under the same conditions by the Czochralski technique in a wide range of dopant concentrations. The distribution coefficients of rare-earth elements in the "crystal-melt" system of LN were determined at the beginning of the crystal growth. Their dependence on the dopant concentration in melt ranging from 0.1 to 3.5 wt% was investigated. Concentration dependences of physicochemical, ferroelectric and structural characteristics of doped LN single crystals were studied using X-ray diffraction, thermal analysis and Raman scattering measurements. A mechanism of rare-earth elements incorporation into the crystal lattice of LN was proposed for a wide range of dopant concentrations. (c) 2006 Elsevier B.V. All rights reserved.