Optical and X-ray diffraction characterizations of crystals I and II of (2Z)-2-(4-bromophenyl)-3-[4-(dimethylamino)phenyl]prop-2-enenitrile (Z-4-BrPhDMAPhACN) are reported. I and II belong to the same monoclinic space group and have nearly identical unit-cell dimensions [I: a = 11.0169(2); b = 6.02041(11); c = 21.8541(4); (β) 98.4082(18). II: a = 11.0475(6); b = 6.0273(3); c = 21.8533(11); (β) 98.315(5)]. Crystals I and II were formed under different conditions and have different crystal habits and colors: crystals I are yellow blocks, whereas crystals II are small, orange needles. I and II show absorption maxima (λabs) in solution at 404 nm and emission (λem) maxima at 501 nm (I) and at 502 nm (II). However, their emission maxima are different in the solid state: I shows an emission at 512 nm and a shoulder at 534 nm, whereas II exhibits a λem maximum at 582 nm. The differences in solid-state photoluminescence were attributed to variations in the crystal morphology and to the crystal habit and size. Both I and II were characterized by nuclear magnetic resonance, mass spectrometry, infrared spectroscopy, UV–vis spectroscopy, fluorescence, cyclic voltammetry, single-crystal and powder X-ray diffraction, differential scanning calorimetry, scanning electron microscopy, and density functional theory calculations.
报告了 (2Z)-2-(4-bromophenyl)-3-[4-(dimethylamino)phenyl]prop-2-enenitrile (Z-4-BrPh
DMAPhACN) 晶体 I 和 II 的光学和 X 射线衍射特征。I 和 II 属于同一单斜空间群,具有几乎完全相同的单胞尺寸[I:a = 11.0169(2);b = 6.02041(11);c = 21.8541(4);(β) 98.4082(18)。II:a = 11.0475(6);b = 6.0273(3);c = 21.8533(11);(β) 98.315(5)]。晶体 I 和 II 是在不同条件下形成的,具有不同的晶体习性和颜色:晶体 I 是黄色块状,而晶体 II 则是橙色小针状。I 和 II 在溶液中的最大吸收波长 (λabs) 为 404 纳米,最大发射波长 (λem)分别为 501 纳米(I)和 502 纳米(II)。不过,它们在固态下的发射最大值不同:I 的发射波长为 512 纳米,肩部波长为 534 纳米,而 II 的 λem 最大值为 582 纳米。固态光致发光的差异归因于晶体形态以及晶体习性和尺寸的变化。通过核磁共振、质谱、红外光谱、紫外-可见光谱、荧光、循环伏安法、单晶和粉末 X 射线衍射、差示扫描量热法、扫描电子显微镜和密度泛函理论计算,对 I 和 II 进行了表征。