Synthesis and single-crystal growth of a new organic nonlinear optical (NLO) material of chalcone derivative, 1-(4-methoxyphenyl)-3(3, 4-dimethoxyphenyl)-2-propen-1-one (DMMC) by slow evaporation technique is reported. Good-quality single crystals of size 28 mm x 7 mm x 3 mm are grown for a period of 20 days and characterized by FT-IR and NMR studies. The grown crystal has been subjected to single-crystal X-ray diffraction technique and cell parameters of the crystal were determined. The title compound crystallizes in monoclinic system with a noncentrosymmetric space group P2(1), with unit cell parameters a= 6.4090(4) angstrom, b = 10.4950(10) angstrom, c = 11.4820(12) angstrom, beta = 98.336(7)degrees, Z = 2 and V = 764.15(12) angstrom(3). The thermal stability of the crystal was determined from TGA/DTA curve. The grown crystals were characterized for their optical transmission and mechanical hardness. The second harmonic generation (SHG) efficiency of the crystals was obtained by classical powder technique using Nd:YAG laser and it is found to be 15 times that of urea. The laser damage threshold value has been determined using Q-switched Nd:YAG laser. (c) 2006 Elsevier B.V. All rights reserved.