1,5-Diphenylpenta-2,4-dien-1-one (DDO) chalcone single crystals, synthesized by a base-catalysed aldol condensation reaction between cinnamaldehyde and acetophenone, have been grown by the slow evaporation of an ethanol solution. The crystals belong to the orthorhombic system with centrosymmetric space groupPbca. The DDO crystals are transparent in the visible region and have a lower optical cut-off at ∼445 nm with a band-gap energy of 2.87 eV. Thermogravimetry/differential scanning calorimetry thermal analysis shows that the crystal is stable up to 375 K and it has a good chemical stability. The vibrational patterns of the chalcone have been investigated by Fourier transform IR and Fourier transform Raman spectroscopy. Microhardness studies were also carried out to elucidate the mechanical behaviour. Theoretical calculations were performed using the Hartree–Fock method with 6-31G(d,p) as the basis set, and the first-order hyperpolarizability is 7.077 × 10−30electrostatic units, which is >25 times that of urea. The crystalline perfection evaluated by high-resolution X-ray diffraction analysis reveals multiple peaks. The molecular packing leads to a centrosymmetric arrangement, resulting in zero second harmonic generation [χ(2)= 0] efficiency. Interestingly, the bromo- and chloro-substituted chalcones are good nonlinear optical materials.
1,5-二苯基戊-2,4-二烯-1-酮(DDO)查尔酮单晶是通过肉桂醛和苯乙酮之间的碱催化醛醇缩合反应合成的,并通过乙醇溶液的缓慢蒸发生长而成。这些晶体属于正方晶系,中心对称空间群为 Pbca。DDO 晶体在可见光区域是透明的,在 ∼445 纳米处具有较低的光学截止点,带隙能为 2.87 eV。热重/差示扫描量热分析表明,该晶体在 375 K 以下都很稳定,并具有良好的化学稳定性。傅立叶变换红外光谱和傅立叶变换拉曼光谱研究了查尔酮的振动模式。此外,还进行了显微硬度研究,以阐明其机械性能。理论计算采用哈特里-福克方法,以 6-31G(d,p) 为基集,一阶超极化率为 7.077 × 10-30 个静电单位,是脲的 25 倍。通过高分辨率 X 射线衍射分析评估其晶体的完美性,可以发现多个峰值。分子填料呈中心对称排列,导致二次谐波发生效率为零[χ(2)=0]。有趣的是,溴代和氯代的查耳酮是良好的非线性光学材料。