合成了 3,4 -二甲氧基 -4′-硝基 艹氐 化合物 ,用 X-射线衍射分析方法测定了该化合物的晶体结构 .该晶体属单斜晶系 ,空间群 P2 1 /c,a=1 .34 6 0 ( 3) nm,b=0 .76 5 8( 2 ) nm,c=1 .4 85 1 ( 3) nm,β=1 1 3.4 6 ( 1 ) 0 ,V=1 .4 0 4 1 1 nm3 ;Z=4 ,Dx=1 .35 g/cm3 ,μ=0 .91 cm- 1 .分子式 C1 6H1 5NO4,Mw=2 85 .30 ,F( 0 0 0 ) =6 0 0 .最终偏离因子 R=0 .0 5 1 ,Rw=0 .0 6 7.结构分析表明 ,晶胞中的四个分子头尾对称堆积 ,形成具有对称中心的空间排列结构 .虽然该化合物分子具有较高的二阶非线性极化率 ,但形成的中心对称晶体不具备二阶非线性光学性质 . The crystal structure of 3,4 - dimethoxy - 4’- nitrides was synthesized and the crystal structure of the compound was determined by X - ray diffraction analysis.The crystal belongs to the monoclinic system with space group P2 1 / c, a = 1.34 6 0 (3) nm, b = 0.76 5 8 (2) nm, c = 1.855 1 (3) nm, β = 1 1 3.4 6 (1) 0, V = 1 .4 0 4 1 1 nm3; Z = 4, Dx = 1 .35 g / cm3, μ = 0 .91 cm-1. Formula C1 6H1 5NO4, Mw = 2 85 .30, F (0 0 0) = 6 0 0. The final deviation factor R = 0 .0 5 1, Rw = 0 .0 6 7. Structural analysis shows that four molecules in the unit cell head and tail symmetrically stacked to form a spatial arrangement with a symmetric center Although the compound The molecule has a higher second-order nonlinear polarizability, but the center-symmetric crystal formed does not have the second-order nonlinear optical properties.