Mixed methyl-(2,4-dinitrophenyl)-aminopropanoate: 2-methyl-4-nitroaniline crystal−a new nonlinear optical material

Abstract

Single crystals of mixed methyl-(2,4-dinitrophenyl)-aminopropanoate (MAP): 2-methyl-4-nitroaniline (MNA) have been grown from solution using a 40:60 mixture of ethanol and ethyl acetate. Formation of an equimolar complex is confirmed by x-ray diffraction studies. The complex crystallizes in the monoclinic space group P21. The lattice parameters are a=6.9196(±0.005) Å; b=7.673(±0.008) Å; c=18.554(±0.001) Å; and β=92.547(±0.006)0. b axis is the unique twofold axis and there are two molecules per unit cell. The molecules stack along the b axis with MAP atop MNA atop MAP. Details of the molecular orientation are given. The Raman spectra also indicate that the parent molecules are not disturbed in the process of crystallization. The second harmonic generation efficiency of the new material for 1064 nm laser radiation is observed to be the same as that of MAP but lower than that of MNA. The latter is attributed to the absorption at 532 nm in the mixed crystal. The melting point determined by differential scanning calorimetry is 104.30 °C.