Single crystals of the semiorganic material, dichlorobis(L-proline)zinc(II) (DCBPZ), were grown from aqueous solution. The grown crystals were tested by single crystal X-ray diffraction, energy-dispersive spectrometry, FT-IR, UV-vis and TG-DTA. The structural prefection of the grown crystals has been analyzed by high-resolution X-ray diffraction (HRXRD) rocking curve measurements. The dielectric and mechanical behavior of the specimen was also studied. The SHG efficiency of DCBPZ is three times greater than that of KDP. Measuring transmittance of DCBPZ permitted the calculation of the refractive index n, the extinction coefficient K and both the real Er and imaginary epsilon(i) components of the dielectric constant as functions of photon energy. The optical band gap of DCBPZ is 4.8 eV. (C) 2008 Elsevier B.V. All rights reserved.