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1.
采用密度泛函理论方法, 计算分析了系列12顶点碳硼烷Ni(Ⅱ)配合物的非线性光学(NLO)性质和电子光谱. 结果表明, 2个P(CH3)3配体的结构变化对配合物的原子间距离影响较小, Ni(Ⅱ)配合物的极化率随取代基共轭性和空间体积的增加而增大. 增强配合物的共轭性及改变P(CH3)3配体结构对二阶NLO系数有明显影响, 其中取代基为苯胺的配合物5b的第一超极化率总有效值(βtot)最大. 分析配合物的电子光谱和相应的分子轨道组成可知, 配体内的电荷转移以及配体到金属的电荷转移对二阶NLO系数贡献较大.  相似文献   

2.
采用量子化学密度泛函理论(DFT)B3LYP/6-31G(d)方法,对4,1,6-MC2B10H1213顶点金属碳硼烷几何构型进行优化,结合有限场(FF)方法计算了它们的极化率和二阶非线性光学(NLO)系数.结果表明,十个13顶点金属碳硼烷分子中1a~6a的二阶NLO系数与其构型纵向扩张呈现相同的规律.分子的前线分子轨道能级差越小,其二阶NLO系数越大.对于不同自旋态的同种金属碳硼烷分子,其偶极矩值为高自旋态大于相应的低自旋态,极化率和二阶NLO系数与自旋多重度没有一致的对应规律,自旋多重度对NLO性质影响不大.  相似文献   

3.
采用密度泛函理论B3LYP/LANL2DZ方法,对实验合成的含有不同生色团的Pt(Ⅱ)配合物的电子性质和二阶非线性光学(NLO)效应进行计算分析。结果表明:配合物中二苯基啡咯啉部分表现出给电子的性质,金属Pt(Ⅱ)在配合物内起到平衡电荷的作用。对配合物lb~6b与配合物a进行比较发现,配合物1b-5b的βvec值比配合物a的成βvec值增大,而配合物6b的βvec值比配合物a的风值减小。7个配合物中前线分子轨道能级差越小的配合物,它的βvec值越大,同时配合物更深层占有轨道与空轨道之间的电子跃迁对二阶NLO效应有明显的贡献。  相似文献   

4.
樊敏  仇永清  孙世玲  刘晓东  苏忠民 《化学学报》2009,67(11):1171-1176
采用量子化学密度泛函理论(DFT) B3LYP/6-31G(d)方法对14顶点双取代碳硼烷和金属硼烷几何构型进行优化, 结合有限场(FF)方法计算了各体系的极化率和二阶超极化率. 同时金属硼烷中金属原子采用赝势基组进行计算, 讨论基组对计算结果的影响. 结果表明, 14顶点碳硼烷和金属硼烷中碳和金属元素的成键方式不同, 金属硼烷中各原子间距离比碳硼烷中大, 平面偏移角增大. 金属原子的引入有效增加分子的NLO系数, 同时金属硼烷的前线分子轨道能级差比碳硼烷小很多, 金属硼烷材料有可能表现出半导体甚至导体特性, 金属原子采用不同基组对计算结果影响不大.  相似文献   

5.
十二顶点邻位双取代碳硼烷衍生物二阶NLO性质的理论研究   总被引:2,自引:2,他引:0  
采用密度泛函理论(DFT) B3LYP/6-31G*方法, 对系列十二顶点邻位双取代碳硼烷(C2B10H12)衍生物的几何构型进行优化. 在所得优化结构的基础上, 结合有限场方法(FF)和含时密度泛函理论(TD-DFT)对这些分子的二阶非线性光学(NLO)活性及电子吸收光谱进行了研究. 结果表明, 邻位双取代碳硼烷有较强的吸电子作用, 与有机基团形成D-π-A结构时, 可以起到很好的受体作用. 当给体部分或桥的共轭性好, 给体的给电子能力强时, 邻位双取代碳硼烷的吸电子作用更明显, 从而增强了分子的二阶NLO响应.  相似文献   

6.
室温下,18-电子体系的半夹心铑配合物Cp*Rh(L)S2C2(B10H10)(L=4-ClCH2-C6H4N (2a),4-CH3SCH2-C6H4N (2b))可以通过16-电子体系的半夹心铑配合物[Cp*Rh[2C2(B10H10)]与吡啶衍生物合成。化合物通过IR、1H NMR和元素分析进行了表征,并用X-射线单晶衍射测定了配合物2a和2b的单晶结构。  相似文献   

7.
采用密度泛函理论(DFT)B3LYP方法,计算分析了7个以碳硼烷和苯环为桥连基团化合物的非线性光学(NLO)特征,结果表明:桥连基团的体积越大,对提高极化率的值越有利;分子桥连部分的电子离域性以及分子的几何构型对二阶NLO系数有重要影响,电子跃迂时的电荷转移程度对二阶NLO性质有较大贡献.通过分析分子的电子光谱和对应的...  相似文献   

8.
本文通过溶剂热法合成了三个基于4’-羧基-2,2’∶6’,2\"-三联吡啶(HL)的单核配合物,其分子式为[ML2]·4H2O(1,M=Zn(Ⅱ);2,M=Cu(Ⅱ);3,M=Fe(Ⅱ)),并分别对其进行了元素分析、波谱、单晶和粉末衍射表征。晶体结构测试结果表明3个配合物为异质同晶结构,都属于四方晶系的I42d空间群。配合物1~3都是1个二价金属离子和2个羧基未配位且去质子化的三齿螯合配体L配位形成的单核结构,通过分子间π-π堆积和氢键作用拓展成三维超分子网络结构。由于二价Zn离子的全充满d10电子构型,配合物1与其配体相比具有明显的室温固态蓝色荧光发射性质。  相似文献   

9.
本文通过溶剂热法合成了三个基于4'-羧基-2,2':6',2\"-三联吡啶(HL)的单核配合物,其分子式为[ML2]·4H2O(1,M=Zn(Ⅱ);2,M=Cu(Ⅱ);3,M=Fe(Ⅱ)),并分别对其进行了元素分析、波谱、单晶和粉末衍射表征。晶体结构测试结果表明3个配合物为异质同晶结构,都属于四方晶系的I42d空间群。配合物1~3都是1个二价金属离子和2个羧基未配位且去质子化的三齿螯合配体L配位形成的单核结构,通过分子间π-π堆积和氢键作用拓展成三维超分子网络结构。由于二价Zn离子的全充满d10配位构型,配合物1与其配体相比具有明显的室温固态蓝色荧光发射性质。  相似文献   

10.
采用密度泛函理论(DFT)B3LYP/6-31G(d)方法对含吡啶配体的过渡金属(M=Cr(0),Mn(Ⅰ),Fe(Ⅱ),Co(Ⅲ))配合物的几何构型进行优化,进一步结合有限场(FF)方法,计算其二阶NLO系数.结果表明,吡啶配体和中心金属原子之间的配位键键长随中心金属价态升高逐渐减小,增加吡啶配体的共轭链长度使极化率变得更大.共轭桥的增长有利于分子内电荷转移,对应体系的二阶NLO系数较大.  相似文献   

11.
The dynamic first hyperpolarizabilities of a series of 1,10-phenanthroline Ru(Ⅱ) complexes were carried out using density functional theory(DFT).The results indicate that these complexes have large second-order nonlinear optical(NLO) responses.Specially,complex 6b has a maximal first hyperpolarizability βtot value.The first hyperpolarizabilities can be tuned by changing the ancillary ligand,introducing electron-acceptor group NO2 and/or increasing π-conjugation on phenanthroline.Calculations on absorption spectra demonstrate that the second-order NLO responses of complexes in series a are ascribed to the intraligand charge transfer(ILCT),while the complexes in series b exhibit metal-to-ligand charge transfer(MLCT) and ligand-to-ligand charge transfer(LLCT) transition at relatively low-energy absorptions.  相似文献   

12.
The (C60CN) formed by the reaction of CN with fullerene shows high electron rich character, very similar to C60˙, and it behaves as a large anion. Similar to Cp, the bulky anion, (C60CN), acts as a strong η5 ligand towards transition metal centers. Previous studies on η5 coordination of fullerene cage are reported for pseudo fullerenes whereas the present study deals with sandwich complexes of (C60CN) with Fe(II), Ru(II), Cr(II), Mo(II), and Ni(II) and multi-decker sandwich complexes of CN–fullerides with Fe(II). The structural parameters of these complexes and the corresponding Cp complexes showed very close resemblance. Analysis of the metal-to-carbon bonding molecular orbitals showed that sandwich complex [Fe(η5-(C60CN))2] exhibit bonding features very similar to that of ferrocene. Also, a 6-fold decrease in the band gap energy is observed for [Fe(η5-(C60CN))2] compared to ferrocene. The energy of dissociation (ΔE) of the ligand (C60CN) from [Fe(η5-(C60CN))2] is slightly lower than the ΔE of a Cp* ligand from a ferrocene derivative wherein each cyclopentadienyl unit is substituted with four tertiary butyl groups. The (C60CN) ligand behaved as one of the bulkiest ligands in the chemistry of sandwich complexes. Further, the coordinating ability of the dianion, (C60(CN)2)2− is evaluated which showed strong coordination ability simultaneously with two metal centers leading to the formation of multi-decker sandwich and pearl-necklace type polymeric structures.  相似文献   

13.
    
In this article, the nonlinear optical (NLO) switching action of Ru(III/II) carboxylate complexes was investigated by density functional theory (DFT). Among the studied complexed, Ru(III)PhCOO? has the largest β value of 4972 × 10?30 esu. Through the proton transfer (PT) process, the ? COOH group of Ru(III)PhCOOH and Ru(III)COOH complexes can form the ? COO? group. Then, ? COO? group acts as a strong donor and Ru(III) acts as an acceptor, which may be the most favorably used in the development of metal complexes NLO material. The redox NLO switching and PT NLO switching of Ru(III)PhCOO?, Ru(III)PhCOOH, Ru(II)PhCOO?, and Ru(II)PhCOOH complexes have been studied. The β value of Ru(III)PhCOO? complex is ~36 and ~48 times larger than those of reduced Ru(II)PhCOO? and Ru(II)PhCOOH, respectively. Note that the β value of deprotonated Ru(III)PhCOO? is ~215 times larger than that of Ru(III)PhCOOH. The molecular electrostatic potential analysis also confirms that Ru(III)PhCOOH may have poor performance in the second‐order NLO response. In addition, the TDDFT calculations show that the ligand to metal charge transfer transition lead to the largest β value of the Ru(III)PhCOO? complex. This investigation provides important insight into the remarkably large NLO properties and NLO switching of Ru(III/II) carboxylate complexes. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem 000: 000–000, 2011  相似文献   

14.
The importance of nonlinear optical phenomena has been known for some time, however, since the mid-1980s, there has been an explosion of interest in the search for and development of non-linear optical materials that possess commercial device applications. To date, the systems have been utilized in information processing, optical switching, optical frequency conversion, and telecommunications, and with the advancing development of optotechnology, burgeoning demands for suitable materials are becoming apparent. Of the many systems studied for example inorganic crystals and semiconductors, organic crystalline monomers, and long-chain polymers with delocalized π electrons, no one species has proved to be all-encompassing, with advantages for one application being negated by disadvantages for another. This is likely to remain the case for the foreseeable future with the criteria of the application governing the type of material used. However, chemists are gradually elucidating what actually governs second- and third-order nonlinear activity and thereby, tailoring species to show greater effects. In recent years, organometallic compounds, through their unique characteristics such as diversity of metals, oxidation states, ligands, and geometries, have found success and brought a new dimension to the area. This review attempts, with critical appraisal, to bring the discussion of organometallic nonlinear optical systems up to date, as well as giving a brief but general introduction to the field of nonlinear optics. For corrigendum see DOI: 10.1002/anie.199508261  相似文献   

15.
用含时藕合微扰Hartrre一Fork(CPHF)方法,有限场MP2理方法以及有向气 体方法,首次分别在分子和晶体水平上计算了一水甲酸锂晶体三次谐波极化率,表 明超分子γ(一3ω;ω,ω,ω)数值与超分子链长有线性关系;晶体x(一3ω;ω, ω,ω)计算值主要受到电子相关影响,其次受到基组和局域场影响,在非共振 条件下,频率色散的影响甚小'最后,估算了一水甲酸锂的三次谐波系数.  相似文献   

16.
DFT B3LYP/LANL2DZ method was employed to calculate electron properties and the second-order nonlinear optical (NLO) respond of platinum (II) complexes which have been synthesized by Weinstein group. 4,7-diphenyl-1,10-phenanthroline shows the ability to push electron in these complexes. Metal Pt plays a balancing charge role. Comparing complex 1b–6b with complex a, the βvec value of complex 1b–5b is larger than one of complex a, while the βvec value of complex 6b is smaller than one of complex a. In these seven complexes, the βvec values of complexes increase with decreasing of the energy difference between HOMO and LUMO. Moreover, the electron transfers from deeper layer occupied orbitals to empty orbitals have a distinct contribution to second-order NLO coefficient. Supported by Program for Changjiang Scholars and Innovative Research Team in University, the Foundation of Jilin Provincial Excellent Youth (Grant No. 20050107) and Youth Science Foundation of Northeast Normal University (Grant No. 111494117)  相似文献   

17.
运用密度泛函PBE0方法研究了双核金属茂合物Zn2(η5-E5)2(E=N, P, As, Sb)的电子结构, 运用自然键轨道(NBO)方法对该体系的电荷分布及成键特征进行了分析. 此类体系中存在Zn—Zn的σ单键, 为近似纯s成分的成键方式. 用含时密度泛函理论(TDDFT ) 完全态求和(SOS) 方法计算了该体系的三阶非线性光学系数, 结果表明, γ值与最大吸收波长λmax成正比, 在各个分量中, 对〈γ〉起主要贡献的是γzzzz, 最大吸收波长对应的电子跃迁是从Zn—Zn的σ成键轨道到Zn—Zn的σ*反键轨道.  相似文献   

18.
采用密度泛函理论(DFT)方法对系列9-氧化芴酮金属Ru配合物氧化还原过程的结构和二阶非线性光学(NLO)性质进行研究.结果表明,氧化还原过程影响配合物的几何结构和电荷分布,配合物的二阶NLO效应可通过氧化还原反应进行调节.配合物副配体取代主配体后,电荷转移程度减小,βtot值减少.与本征态相比,氧化过程可提高配合物的二阶NLO响应,还原过程中含有2个主配体配合物的βtot值减小,而含有2个副配体配合物的βtot值增大.分析主要电子跃迁过程可知,氧化还原过程影响了配合物的供受体性质.  相似文献   

19.
采用密度泛函理论B3LYP/6-31+G(d)方法,对实验合成的具有不同取代基团偶氮苯系列分子的电子性质和二阶非线性光学(NLO)效应进行计算分析.结果表明:偶氮(N—N)在分子中分别起到拉电子和传递电荷的作用.对8个分子进行比较发现,含有氨基的分子1b-4b的二阶NLO系数明显的高于含有羟基的分子1a-4a.各分子前线分子轨道跃迁对二阶NLO效应有主要贡献.  相似文献   

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