Abstract: The title 1:1 adduct was prepared and a large single crystal with dimensions of 24 mm×15 mm×38 mm was obtained by slow-cooling method.It produces the green radiation at 512 nm under the irradiation of Nd³⁺ : YAGlaser beam at 1064 nm.The crystal structure of this potential non-linear optical material was studied by X-ray diffraction method.The crystal is triclinic, space group P1, with a=0.4609(2) nm, b=0.7405(5) nrn, c=l.0684(6) nm, α= 95.50(5)°, β=98.72(3)°, γ=104.33(5)°, Z=l; R=0.076.The molecules of 3,5-dini-trobenzoic acid and diethanolamine are connected to each other by intermolecular hydrogen bonds to form two-dimensional net-work which are parallel to the 001 plane.

Key words: 3,5-Dinitrobenzoic acid and diethanolamine, Crystal structure, Non-linear optics