Abstract Three thiophenyl chalcone derivatives, (E)-1-(5-bromo-2-thienyl)-3-(4-bromophenyl)prop-2-en-1-one (B5B2SC), (E)-1-(5-bromo-2-thienyl)-3-(3-chlorophenyl)prop-2-en-1-one (3C5B2SC), and (E)-1-(5-bromo-2-thienyl)-3-(2-methoxyphenyl)prop-2-en-1-one (2M5B2SC), were successfully synthesized and crystallized. The structures were confirmed by experimental and theoretical FTIR and 1H NMR spectra. The crystal structures were determined by single-crystal XRD method. The B5B2SC, 3C5B2SC and 2M5B2SC crystallize in the monoclinic space groups P 21/c (centrosymmetric), P 2 (non-centrosymmetric) and triclinic space group P 1 ‾ (centrosymmetric), respectively. All these structures adopt trans configuration with respect to C6═C7 double bond. The chalcones have high thermal stability, a wide transparency in the visible region and small optical band gaps. The 3C5B2SC exhibits powder second-harmonic generation (SHG) intensity of about 1.7 times higher than Urea. From continuous wave (CW) laser (532 nm) Z-scan experimental data analyses, the third-order NLO parameters such as nonlinear absorption coefficient (β = ~10−4 cm/W), nonlinear refractive index (n2= ~10−9 cm2/W), third-order NLO susceptibility (χ(3) = ~10−7 esu), molecular hyperpolarizability (γh = ~10−27 esu), ground state absorption cross section (σg = ~10−22 cm2) and excited state cross sections (σex= ~10−20 cm2) were determined. The chalcones also exhibited optical limiting and all optical switching behaviour for CW laser operating at 532 nm wavelengths. The electric dipole moment, polarizability, hyperpolarizabilty, HOMO-LUMO energy gap, global chemical reactivity descriptors (GCRD), molecular electrostatic potentials (MEP) and natural bond orbital (NBO) analysis were computed theoretically (DFT). The results indicate that these three chalcones with thiophene moiety are potential materials for optical device applications.

中文翻译：

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三种噻吩查尔酮衍生物的晶体结构、线性和非线性光学性质：结合实验和计算研究

摘要 三苯硫基查尔酮衍生物，(E)-1-(5-bromo-2-thienyl)-3-(4-bromophenyl)prop-2-en-1-one (B5B2SC)，(E)-1-(5 -bromo-2-thienyl)-3-(3-chlorophenyl)prop-2-en-1-one (3C5B2SC)，和 (E)-1-(5-bromo-2-thienyl)-3-(2-甲氧基苯基)prop-2-en-1-one (2M5B2SC) 成功合成并结晶。通过实验和理论 FTIR 和 1 H NMR 光谱证实了结构。通过单晶XRD方法确定晶体结构。B5B2SC、3C5B2SC 和 2M5B2SC 分别在单斜空间群 P 21/c（中心对称）、P 2（非中心对称）和三斜空间群 P 1 ‾（中心对称）中结晶。所有这些结构都采用 C6=C7 双键的反式构型。查耳酮具有高热稳定性、可见光区的宽透明度和小的光学带隙。3C5B2SC 的粉末二次谐波发生 (SHG) 强度比尿素高约 1.7 倍。从连续波 (CW) 激光 (532 nm) Z 扫描实验数据分析，非线性吸收系数 (β = ~10−4 cm/W)、非线性折射率 (n2= ~10−) 等三阶 NLO 参数9 cm2/W)、三阶 NLO 磁化率 (χ(3) = ~10−7 esu)、分子超极化率 (γh = ~10−27 esu)、基态吸收截面 (σg = ~10−22 cm2)和激发态横截面 (σex= ~10−20 cm2) 被确定。对于在 532 nm 波长下工作的 CW 激光器，查耳酮还表现出光学限制和所有光学切换行为。电偶极矩、极化率、超极化率、HOMO-LUMO 能隙、全局化学反应性描述符 (GCRD)、分子静电势 (MEP) 和自然键轨道 (NBO) 分析通过理论计算 (DFT)。结果表明这三种具有噻吩部分的查耳酮是光学器件应用的潜在材料。