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运用密度泛函理论B3LYP方法对8-羟基喹啉(银、铂)(AgQ、PtQ2)金属配合物及其衍生物的非线性光学性质进行理论计算研究. 结果表明: 引入取代基使铂配合物的最强吸收波长产生较大红移. 最低能量跃迁吸收来自最高占据分子轨道(HOMO)到最低空分子轨道(LUMO)的d→π*和π→π*跃迁, 属于金属配体电荷转移(MLCT)与配体配体电荷转移(LLCT). 金属银和铂掺杂8-羟基喹啉使其三阶非线性光学系数γ值明显增大, 并且在配合物上引入―Ph, ―PhOCH3, ―PhF2, ―PhF5基团将进一步增大γ值. 引入基团的供电子性越强, γ值增大的幅度越大, 引入基团的吸电子性越强, γ值增大的幅度越小. 相似文献
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6,7,8,9-四氢-吩嗪并[2,3]C_(60)衍生物的结构、电子光谱和二阶非线性光学性质的理论研究 总被引:2,自引:0,他引:2
利用半经验AM1量子化学方法研究了6, 7, 8, 9-四氢-吩嗪并[2, 3]C60衍生物(1~4)及其异构体5, 6, 7, 8-四氢-9, 10-二氮杂蒽并[2, 3]C60衍生物 (5~8) 的结构。 结果表明,目标分子的前线轨道主要由C60部分决定, C60母体与加成基团之间存在较强的分子内电荷转移, C60部分是电子受体,吩嗪环部分为电子给体。 在AM1优化几何构型的基础上, 用INDO/SCI方法计算了目标分子的电子光谱, 用完全态求和(SOS)公式计算了其二阶非线性光学性质。 计算结果表明, 目标分子在400 nm 以上均存在弱吸收峰, 与实验所得结果一致。 5, 6, 7, 8-四氢-9, 10-二氮杂蒽并[2, 3]C60衍生物(5~8)的二阶非线性光学系数(0)比其异构体6, 7, 8, 9-四氢-吩嗪并[2, 3]C60衍生物(1~4)的大得多。 相似文献
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对硝基二苯乙炔系列衍生物的二阶非线性光学性质的理论研究 总被引:6,自引:1,他引:5
在ZINDO方法基础上,按完全态求和(SOS)公式编制了计算分子二阶非线性光学系数βijk和βμ的程序,研究了对硝基二苯乙炔系列衍生物的结构和非线性光学性质,考察了分子共轭链长和给电子基团对βμ的影响.结果表明,对硝基二苯乙炔系列衍生物上连有推电子基团有利于增大二阶光学非线性,扩大共轭范围也有利于增大二阶光学非线性,但对透明性则影响不大. 相似文献
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BeQ2衍生物中金属配体间相互作用对前线分子轨道和非线性光学性质影响的理论研究 总被引:1,自引:0,他引:1
采用从头算HF及密度泛函理论(DFT)B3LYP方法对8-羟基喹啉铍(BeQ2)及其取代衍生物Be(MQ)2,Be(CNQ)2的稳定结构及结合能进行计算.在此基础上,系统分析了前线分子轨道组成及体系非线性光学系数的变化.计算结果表明,金属-配体间的相互作用使非线性光学系数增大,且γ比β增大得多;CH3和CN的推拉电子取代均使结合能降低,电子离域性增强,非线性光学性质得以改善. 相似文献
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合成1种查尔酮衍生物1-(芘-1-基)-3-(苯并噻吩-3-基)丙烯酮(PBTAK),经IR,1 H NMR,13C NMR和HR-MS对其结构进行表征.采用4f相位相干成像技术测定了它的三阶非线性光学性质并确定了相关参数:脉宽为4nm,激光波长为460nm,非线性吸收系数β=0.23×10~(-9) m/W,非线性折射率n2=-0.50×10~(-16) m~2/W,三阶非线性极化率χ~((3))=9.37×10~(-21) C;同时测定了紫外光谱、荧光光谱和DSC曲线.运用密度泛函方法计算了PBTAK的分子轨道能量和极化率,结果表明电子转移能在分子内部进行,显示出良好的非线性光学活性. 相似文献
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采用密度泛函理论(DFT)B3LYP/6-31G*优化一系列以芳环为桥联基团,1,3-二硫杂环戊二烯为供电子基团,丙二氰为吸电子基团的D-π-A型分子的几何结构,在此基础上对分子的极化率和第一超极化率进行计算.结果分析表明,桥联苯环数的增加,供电子基团(—OCH3)的引入及共轭桥的增长对分子的几何构型影响很小,但能使分子的二阶非线性光学(NLO)系数增加,且分子的最大吸收波长发生红移.甲氧基的引入或共轭桥的增长,分子的前线分子轨道能级差减小,TD-DFT计算表明分子深层占有轨道与空轨道之间的电子跃迁对二阶NLO效应也有较明显贡献. 相似文献
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推、拉电子基团对水杨醛缩胺分子电子结构和非线性光学性质的影响 总被引:3,自引:2,他引:1
采用量子化学半经验FF/PM3方法,讨论了水杨醛缩苯胺分子中两苯环的对位被推、拉电子基团取代后,体系电子结构和非线性光学性质的变化,考查了分子电子结构对非线性光学性质影响的微观本质,得到的具有给体-共轭桥键-受体型结构的水杨醛缩苯胺分子应显示良好的非线光学性质。 相似文献
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As a new nonlinear optical organic material, MHBA (3-Methoxy-4-Hydroxy-Benzaldehyde) crystal[1] has been grown into a size of 70 mm×40 mm×20 mm. Its second-harmonic generation (SHG) is about 30 times larger than that of urea, and has a suitable transparency in the range from 370 nm to 1700 nm. MHBA can be used to realize direct frequency doubling of near infrared diode laser to generate violet-blue light at room temperature. We have discussed its SHG by using finite-field method[2~3]. However there is no report on the third-harmonic generation (THG) properties of MHBA. In this study we will theoretically investigate the molecular second-order hyperpolarizabilities of MHBA. 相似文献
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A single crystal of Pyridine-1-ium-2-carboxylatehydrogenbromide (PHBr) was grown using the Slow Evaporation Solution Technique. Using Single Crystal X-Ray Diffraction analysis, the crystal lattice characteristics and molecular structure of the grown crystal of PHBr were found and it corresponds to the Triclinic crystal system with space group Pī. Intra and intermolecular interactions were visualized using Hirshfeld surface analysis. The theoretical calculation conducted by Density Functional Theory (DFT) and it is well agreed with the experimental results. The Molecular optimized geometry, FT-IR and HOMO-LUMO energy gap were computed using the B3LYP level of theory with a 6-31 + G (d,p) basis set. The FT-IR spectrum studies are given here to look at the modes of vibration of numerous functional groups found in the PHBr crystal. The measurements of UV–visible NIR transmittance show that the crystal has a high transmittance over the whole visible spectrum. The Z-scan approach is used to perform third-order nonlinear optical (NLO) investigations on a PHBr crystal and optical properties such as linear and nonlinear refractive index are computed. 相似文献
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Clodoaldo Valverde Rafael S. Vinhal Luiz F. N. Naves Jean M. F. Custdio Basílio Baseia Heibbe Cristhian B. de Oliveira Caridad N. Perez Hamilton B. Napolitano Francisco A. P. Osrio 《Molecules (Basel, Switzerland)》2022,27(8)
A novel 4(1H) quinolinone derivative (QBCP) was synthesized and characterized with single crystal X-ray diffraction. Hirshfeld surfaces (HS) analyses were employed as a complementary tool to evaluate the crystal intermolecular interactions. The molecular global reactivity parameters of QBCP were studied using HOMO and LUMO energies. In addition, the molecular electrostatic potential (MEP) and the UV-Vis absorption and emission spectra were obtained and analyzed. The supermolecule (SM) approach was employed to build a bulk with 474,552 atoms to simulate the crystalline environment polarization effect on the asymmetric unit of the compound. The nonlinear optical properties were investigated using the density functional method (DFT/CAM-B3LYP) with the Pople’s 6-311++G(d,p) basis set. The quantum DFT results of the linear polarizability, the average second-order hyperpolarizability and the third-order nonlinear susceptibility values were computed and analyzed. The results showed that the organic compound (QBCP) has great potential for application as a third-order nonlinear optical material. 相似文献
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S. Clevers F. Simon V. Dupray G. Coquerel 《Journal of Thermal Analysis and Calorimetry》2013,112(1):271-277
We report the use of second harmonic generation (SHG) and temperature resolved second harmonic generation (TR-SHG) for in situ probing and monitoring the structural purification of m-hydroxybenzoic acid (MHBA). Pure and mixtures of the two polymorphic forms of MHBA (metastable Pna21 and stable P21/c) and commercial MHBA were analysed by: DSC, XRPD and SHG. Results obtained with these three techniques are compared and demonstrate for that particular component, the high sensitivity and accuracy of SHG in assessing the polymorphic purity of MHBA. The SHG detection threshold for the metastable polymorph is circa 2 ppm and is several orders of magnitude better than the sensitivity of XRPD (1 wt%) and DSC (only 17 wt%). The proportion of the metastable phase in the commercial MHBA was evaluated to 1 wt% by SHG. Results of TR-SHG measurements performed on commercial MHBA at 5 K min?1 heating rate show that TR-SHG is a good technique for an in situ monitoring of the structural purity. The present study clearly demonstrates that SHG and TR-SHG are relevant and accurate techniques for probing the structural purity and for the monitoring of solid–solid phase transitions provided one of the two varieties crystallizes in a non-centrosymmetric space group. 相似文献
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P. S. Latha Mageshwari R. Priya S. Krishnan V. Joseph S. Jerome Das 《Journal of Thermal Analysis and Calorimetry》2017,128(1):29-37
Sodium hydrogen succinate, an alkali metallo-organic third-order nonlinear optical crystal, had been grown successfully using aqueous solution by slow evaporation technique at room temperature. Transparent single crystals were selected and subjected to single-crystal X-ray diffraction analysis to identify lattice parameters, space group and morphology. The grown crystal was further subjected to powder X-ray diffraction to analyze the crystalline quality, UV–Vis–NIR spectral analysis to reveal optical transparency, FTIR spectroscopy for confirmation of the functional group analysis and TG–DTG/DSC analysis to determine the thermal stability. The dielectric constant and dielectric loss were studied as a function of frequency at different temperatures, and the results were discussed. The mechanical properties were calculated by Vickers microhardness test, and the third-order nonlinear optical parameters such as nonlinear refractive index, nonlinear absorption coefficient and real and imaginary parts of the third-order nonlinear optical susceptibility were determined by Z-scan technique. 相似文献
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Ben Ahmed A Elleuch N Feki H Abid Y Minot C 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2011,79(3):554-561
This paper presents the results of our calculations on the geometric parameters, vibrational spectra and hyperpolarizability of a nonlinear optical material L-histidine oxalate. Due to the lack of sufficiently precise information on geometric structure in literature, theoretical calculations were preceded by re-determination of the crystal X-ray structure. Single crystal of L-histidine oxalate has been growing by slow evaporation of an aqueous solution at room temperature. The compound crystallizes in the non-Centro symmetric space group P2(1)2(1)2(1) of orthorhombic system. The FT-IR and Raman spectra of L-histidine oxalate were recorded and analyzed. The vibrational wave numbers were examined theoretical with the aid of Gaussian98 package of programs using the DFT//B3LYP/6-31G(d) level of theory. The data obtained from vibrational wave number calculations are used to assign vibrational bands obtained in IR and Raman spectroscopy of the studied compound. The geometrical parameters of the title compound are in agreement with the values of similar structures. To investigate microscopic second order non-linear optical NLO behaviour of the examined complex, the electric dipole μ(tot), the polarizability α(tot) and the hyperpolarizability β(tot) were computed using DFT//B3LYP/6-31G(d) method. According to our calculation, the title compound exhibits non-zero β(tot) value revealing microscopic second order NLO behaviour. 相似文献
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John CJ Amalanathan M Sajan D Lakshmi KU Joe IH 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2011,78(1):264-272
FT-Raman and FT-IR spectra of the nonlinear optical crystal 1-(4-N,N-dimethylaminopyridinium) acetic acid bromide monohydrate have been recorded and analyzed. The equilibrium geometry, vibrational wavenumbers and the first order hyperpolarizability of the crystal have been calculated with the help of density functional theory computations. The assignments of the vibrational spectra have been carried out with the help of Scaled Quantum Mechanic force field theory. Optimized geometry gives the charge transfer interaction of the pyridine ring and the amino group in the electron-donor side of the nonlinear optic chromophore. Electron–phonon coupling and O–H?O interactions in making the molecule nonlinear optical active have been analyzed based on the vibrational spectral features. The Natural Bond Orbital analysis confirms the occurrence of strong intermolecular O–H?O hydrogen bonding. 相似文献
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新合成了一种六棱柱型金属团簇化合物Mo2Ag4S8(dppy)4, 并用X射线单晶衍射结构分析方法测定了其晶体结构. 应用Z-scan技术研究了该金属团簇化合物在波长为532 nm的纳秒激光脉冲作用下的三阶非线性光学特性. 为了研究Mo2Ag4S8(dppy)4的非线性起源, 应用泵浦探测技术研究了该金属团簇化合物在波长为532 nm的皮秒激光脉冲作用下的光学非线性响应. 实验结果表明金属团簇化合物Mo2Ag4S8(dppy)4具有自聚焦特性和非线性吸收特性; 非线性折射率n2, 非线性吸收系数β和非线性极化率χ(3)分别为1.45×10-10 esu, 6.2×10-10 m/W及2.1×10-11 esu. 实验结果表明金属团簇化合物Mo2Ag4S8(dppy)4的光学非线性响应是非线性吸收和非线性散射共同作用的结果. 相似文献
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Shou-chun Yin 徐洪耀 Gang Li Xin-yan Su Ya-chen Gao Yin-lin Song Ben-zhong Tang 《高分子科学》2006,(3):221-227
Two novel polyacetylenes bearing nonlinear optical chromophoric group poly(3-(4-[4-(n-butyloxy) phenylazophenyl]carbonyl)oxy-1-propyne) (poly(1a)) and poly(3-(4-[4-(n-heptyloxy)phenylazophenyl]carbonyl)-oxy-l- propyne) (poly(lb)) were synthesized with [Rh(nbd)Cl]2-EtaN as catalysts. These polyacetylenes are soluble by using an alkyl spacer and an alkyloxyl group as a substituent. They were characterized by FTIR, NMR, GPC and UV-Vis and their optical limiting and nonlinear optical properties were investigated using 8 ns pulse at 532 nm wavenumber. The results show that these soluble functional polyacetylenes possess optical limiting properties and large nonlinear optical properties and poly(1b) possesses better optical limiting and nonlinear optical properties than poly( 1 a). 相似文献