Growth and Characterization of Urea-(DL) Tartaric Acid Single Crystals

A new organic UV nonlinear optical crystal urea-(DL)tartaric acid [CO(NH₂)₂₋(DL) C₄H₆O₆] (abbreviated as U(DL)T) is reported. Large single crystals have been grown from aqueous solution by the cooling method. They belong to the monoclinic space group P2₁ and the lattice parameters are: a = 7.6973 Å, b = 23.3310 Å, c = 4.8727 Å, and β = 100.82°. The structure and some of its physical properties have been determined. The crystal is transparent from 0.24 to 1.95 μm. The efficiency of powder SHG is larger by one order of magnitude than that of KDP. Thus the crystal will be a useful NLO material.