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1.
通过两次羟醛缩合反应合成了一种含呋喃共轭桥的有机非线性光学生色团分子2-二氰亚甲基-3-氰基-4-[2-(4-二乙氨基-苯乙烯基-呋喃基-5)-乙烯基]-5,5-二甲基-2,5-二氢呋喃(EFFC), 用IR谱、1H NMR谱以及元素分析表征确认了其结构. 热失重分析表明, 材料的热分解温度Td为250℃. 用密度泛函理论的B3LYP方法在6-31G基组下对这种生色团分子进行了结构优化, 并在相同基组下对分子的静态二阶极化率进行了计算, 分子的b0=6.5×10-28 esu. 将分子以18%的质量比与聚砜进行主-客体掺杂, 用溶胶凝胶法制备成膜后进行极化, 用二次谐波法对掺杂极化聚合物薄膜的电光系数进行测量, 其r33值最高达到80 pm/V. 相似文献
2.
Dr. Ester Rossi Dr. Alessia Colombo Dr. Claudia Dragonetti Dr. Stefania Righetto Prof. Dr. Dominique Roberto Prof. Dr. Renato Ugo Dr. Adriana Valore Prof. Dr. J. A. Gareth Williams Dr. Maria Grazia Lobello Dr. Filippo De Angelis Dr. Simona Fantacci Prof. Dr. Isabelle Ledoux‐Rak Dr. Anu Singh Prof. Dr. Joseph Zyss 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(30):9875-9883
Appropriate functionalization of the cyclometalated ligand, L , and the choice of the ancillary ligand, X, allows the dipolar second‐order nonlinear optical response of luminescent [Pt L X] complexes—in which L is an N^C^N‐coordinated 1,3‐di(2‐pyridyl)benzene ligand and X is a monodentate halide or acetylide ligand—to be controlled. The complementary use of electric‐field‐induced second‐harmonic (EFISH) generation and harmonic light scattering (HLS) measurements demonstrates how the quadratic hyperpolarizability of this appealing family of multifunctional chromophores, characterized by a good transparency throughout much of the visible region, is dominated by an octupolar contribution. 相似文献
3.
Nonempirically tuned hybrid density functionals with range‐separated exchange are applied to calculations of the first hyperpolarizability (β∥) and charge‐transfer (CT) excitations of linear “push–pull” donor–acceptor‐substituted organic molecules with extended π‐conjugated bridges. An unphysical delocalization with increasing chain length in density functional calculations can be reduced significantly by enforcing an asymptotically correct exchange‐correlation potential adjusted to give frontier orbital energies representing ionization potentials. The delocalization error for a number of donor–acceptor systems is quantified by calculations with fractional electron numbers and from orbital localizations. Optimally tuned hybrid variants of the PBE functional incorporating range‐separated exchange can produce similar magnitudes for β∥ as Møller–Plesset second‐order perturbation (MP2) correlated calculations. Improvements are also found for CT excitation energies, with results similar to an approximate coupled‐cluster model (CC2). 相似文献
4.
Dr. Marina Yu. Balakina 《Chemphyschem》2012,13(18):4186-4194
An analytical approach aimed at modeling the nonlinear optical (NLO) response of a polymer electret with incorporated organic dipole chromophores is extended to the dynamic case. The approach allows the effect of the locally anisotropic, polarizable, deformable polymer matrix on the chromophore NLO response to be accounted for. The method exploits the original cavity ansatz according to which the virtual cavity occupied by the chromophore in the polymer matrix is chosen to be conformal to the characteristic ellipsoid of the generalized permittivity tensor. Analytical expressions for the dynamic electric moments of dipole chromophores and macroscopic polarization of a polymer electret at fundamental and second harmonic frequencies are obtained by using a computational scheme based on two self‐consistency procedures. On the basis of the expressions for dynamic macroscopic polarization, the analytical formulas for linear, ${\chi _j^{i(1)} (\omega )}$ , and quadratic, ${\chi _{jk}^{i(2)} (2\omega )}$ , electric susceptibilities are obtained. The presented expressions establish the relationship between the molecular polarizabilities of chromophores and the macroscopic electrical properties of the polymer electret. 相似文献
5.
Stability and Nonlinear Optical Response of Alkalides that Contain a Completely Encapsulated Superalkali Cluster 下载免费PDF全文
Dr. Wei‐Ming Sun Prof. Ying Li Xiang‐Hui Li Prof. Di Wu Dr. Hui‐Min He Prof. Chun‐Yan Li Prof. Jing‐Hua Chen Prof. Zhi‐Ru Li 《Chemphyschem》2016,17(17):2672-2678
Guided by density functional theory (DFT) computations, a new series of superalkali‐based alkalides, namely FLi2+(aza222)K?, OLi3+(aza222)K?, NLi4+(aza222)K?, and Li3+(aza222)K? were designed with various superalkali clusters embedded into an aza222 cage‐complexant. These species possess diverse isomeric structures in which the encapsulated superalkalis preserve their identities and behave as alkali metal atoms. The results show that these novel alkalides possess larger complexation energies and enhanced hyperpolarizabilities (β0) compared with alkali‐metal‐based and previous superalkali‐based clusters. Especially, a prominent structural dependence of β0 is observed for these studied compounds. Hence, the geometric factors that affect the nonlinear optical (NLO) response of such alkalides is elucidated in detail in this work. This study not only provides novel candidates for alkalides, it also offers an effective way to enhance the NLO response and stability of alkalides. 相似文献
6.
Difluorenyl carbo‐Benzenes: Synthesis,Electronic Structure,and Two‐Photon Absorption Properties of Hydrocarbon Quadrupolar Chromophores 下载免费PDF全文
Dr. Iaroslav Baglai Manuel de Anda‐Villa Rodrigo M. Barba‐Barba Corentin Poidevin Dr. Gabriel Ramos‐Ortíz Dr. Valérie Maraval Dr. Christine Lepetit Dr. Nathalie Saffon‐Merceron Dr. José‐Luis Maldonado Prof. Dr. Remi Chauvin 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(40):14186-14195
The synthesis, crystal and electronic structures, and one‐ and two‐photon absorption properties of two quadrupolar fluorenyl‐substituted tetraphenyl carbo‐benzenes are described. These all‐hydrocarbon chromophores, differing in the nature of the linkers between the fluorenyl substituents and the carbo‐benzene core (C?C bonds for 3 a , C?C?C?C expanders for 3 b ), exhibit quasi–superimposable one‐photon absorption (1PA) spectra but different two‐photon absorption (2PA) cross‐sections σ2PA. Z‐scan measurements (under NIR femtosecond excitation) indeed showed that the C?C expansion results in an approximately twofold increase in the σ2PA value, from 336 to 656 GM (1 GM=10?50 cm4 s molecule?1 photon?1) at λ=800 nm. The first excited states of Au and Ag symmetry accounting for 1PA and 2PA, respectively, were calculated at the TDDFT level of theory and used for sum‐over‐state estimations of σ2PA(λi), in which λi=2 hc/Ei, h is Planck’s constant, c is the speed of light, and Ei is the energy of the 2PA‐allowed transition. The calculated σ2PA values of 227 GM at 687 nm for 3 a and 349 GM at 708 nm for 3 b are in agreement with the Z‐scan results. 相似文献
7.
Tetrazine Chromophore‐Based Metal–Organic Frameworks with Unusual Configurations: Synthetic,Structural, Theoretical,Fluorescent, and Nonlinear Optical Studies 下载免费PDF全文
Dr. Jianghua Li Ding Jia Dr. Suci Meng Dr. Jinfang Zhang Dr. Marie P. Cifuentes Prof. Dr. Mark G. Humphrey Prof. Dr. Chi Zhang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(21):7914-7926
Three unusual three‐dimensional (3D) tetrazine chromophore‐based metal–organic frameworks (MOFs) {(Et4N)[WS4Cu3(CN)2(4,4′‐pytz)0.5]}n ( 1 ), {[MoS4Cu4(CN)2(4,4′‐pytz)2] ? CH2Cl2}n ( 2 ), and {[WS4Cu3(4,4′‐pytz)3] ? [N(CN)2]}n ( 3 ; 4,4′‐pytz=3,6‐bis(4‐pyridyl)tetrazine) have been synthesized and characterized by using FTIR and UV/Vis spectroscopy, elemental analysis, powder X‐ray diffraction, gel permeation chromatography, steady‐state fluorescence, and thermogravimetric analysis; their identities were confirmed by single‐crystal X‐ray diffraction studies. MOF 1 possesses the first five‐connected M/S/Cu (M=Mo, W) framework with an unusual 3D (44?66) topology constructed from T‐shaped [WS4Cu3]+ clusters as nodes and single CN?/4,4′‐pytz bridges as linkers. MOF 2 features a novel 3D MOF structure with (420?68) topology, in which the bridging 4,4′‐pytz ligands exhibit unique distorted arch structures. MOF 3 displays the first 3D MOF structure based on flywheel‐shaped [WS4Cu3]+ clusters with a non‐interpenetrating honeycomb‐like framework and a heavily distorted “ACS” topology. Steady‐state fluorescence studies of 1 – 3 reveal significant fluorescence emissions. The nonlinear optical (NLO) properties of 1 – 3 were investigated by using a Z‐scan technique with 5 ns pulses at λ=532 nm. The Z‐scan experimental results show that the π‐delocalizable tetrazine‐based 4,4′‐pytz ligands contribute to the strong third‐order NLO properties exhibited by 1 – 3 . Time‐dependent density functional theory studies afforded insight into the electronic transitions and spectral characterization of these functionalized NLO molecular materials. 相似文献
8.
Wenbo Wu Prof. Conggang Li Prof. Gui Yu Prof. Yunqi Liu Prof. Cheng Ye Prof. Jingui Qin Prof. Zhen Li 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(35):11019-11028
Herein, high‐generation dendrimers G4‐NS and G5‐NS , which contained 30 and 62 azo‐benzene chromophore moieties, respectively, were conveniently prepared in high purity and satisfied yields by a combination of divergent and convergent approaches, coupled with the utilization of the powerful Sharpless click reaction. These dendrimers possessed a regular structure of alternating layers of nitro‐based and sulfonyl‐based azo chromophores in which the sulfonyl‐based azo‐chromophore moieties were utilized as co‐isolation groups for the nitro‐based moieties to achieve larger macroscopic second‐order nonlinear optical (NLO) effects. These high‐generation dendrimers ( G4‐NS and G5‐NS ) displayed very large NLO efficiencies (up to 253.0 pm V?1), which is, to the best of our knowledge, the record highest efficiency for simple azo‐chromophore moieties. 相似文献
9.
10.
Wenbo Wu Dr. Guohua Xu Prof. Conggang Li Prof. Gui Yu Prof. Yunqi Liu Prof. Cheng Ye Prof. Jingui Qin Prof. Zhen Li 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(21):6874-6888
Through the combination of the divergent and convergent approaches, coupled with the utilization of the powerful Sharpless “click‐chemistry” reaction, two series of sulfonyl‐based high‐generation NLO dendrimers were conveniently prepared with high purity and in satisfactory yields. Thanks to the perfect three‐dimensional (3D) spatial isolation from the highly branched structure and the isolation effect of the exterior benzene moieties and the interior triazole rings, these dendrimers exhibited large second harmonic generation coefficient (d33) values up to 181 pm V?1, which, to the best of our knowledge, is the highest value so far for polymers containing sulfonyl‐based chromophore moieties. Meanwhile, compared with the nitro‐chromophore‐based analogues, their optical transparency and NLO stability were improved in a large degree, due to the lower dipole moment (μ) and the special main‐chain structure of sulfonyl‐based chromophore in these dendrimers. 相似文献
11.
Dr. Gilles Ulrich Dr. Alberto Barsella Dr. Alex Boeglin Dr. Songlin Niu Dr. Raymond Ziessel 《Chemphyschem》2014,15(13):2693-2700
A set of linear and dissymmetric BODIPY‐bridged push–pull dyes are synthesized. The electron‐donating substituents are anisole and dialkylanilino groups. The strongly electron‐accepting moiety, a 1,1,4,4‐tetracyanobuta‐1,3‐diene (TCBD) group, is obtained by insertion of an electron‐rich ethyne into tetracyanoethylene. A nonlinear push–pull system is developed with a donor at the 5‐position of the BODIPY core and the acceptor at the 2‐position. All dyes are fully characterized and their electrochemical, linear and nonlinear optical properties are discussed. The linear optical properties of dialkylamino compounds show strong solvatochromic behavior and undergo drastic changes upon protonation. The strong push–pull systems are non‐fluorescent and the TCBD‐BODIPY dyes show diverse photochemistry and electrochemistry, with several reversible reduction waves for the tetracyanobutadiene moiety. The hyperpolarizability μβ of selected compounds is evaluated using the electric‐field‐induced second‐harmonic generation technique. Two of the TCBD‐BODIPY dyes show particularly high μβ (1.907 μm) values of 2050×10?48 and 5900×10?48 esu. In addition, one of these dyes shows a high NLO contrast upon protonation–deprotonation of the donor residue. 相似文献
12.
Spin‐restricted time‐dependent DFT for open‐shell systems is used to study the spin multiplicity dependence of nonlinear optical coefficients. Calculations are performed for various spin states of the pyrrole radical (see figure). The results indicate a substantial dependence on spin multiplicity of the NLO properties, which are sensitive to the basis set compared to closed shells at the DFT level of theory.
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14.
Dr. Shabbir Muhammad Kotaro Fukuda Takuya Minami Dr. Ryohei Kishi Dr. Yasuteru Shigeta Dr. Masayoshi Nakano 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(5):1677-1685
To reveal new structure–property relationships in the nonlinear optical (NLO) properties of fullerenes that are associated with their open‐shell character, we investigated the interplay between the diradical character (yi) and second hyperpolarizability (longitudinal component, γzzzz) in several fullerenes, including C20 , C26 , C30 , C36 , C40 , C42 , C48 , C60 , and C70 , by using the broken‐symmetry density functional theory (DFT; LC‐UBLYP (μ=0.33)/6‐31G*//UB3LYP/6‐31G*). We found that the large differences between the geometry and topology of fullerenes have a significant effect on the diradical character of each fullerene. On the basis of their different diradical character, these fullerenes were categorized into three groups, that is, closed‐shell (yi=0), intermediate open‐shell (0<yi<1), and almost pure open‐shell compounds (yi?1), which originated from their diverse topological features, as explained by odd‐electron‐density and spin‐density diagrams. For example, we found that closed‐shell fullerenes include C20 , C60 , and C70 , whereas fullerenes C26 and C36 and C30 , C40 , C42 , and C48 are pure and intermediate open‐shell compounds, respectively. Interestingly, the γzzzz enhancement ratios between C30 / C36 and C40 / C60 are 4.42 and 11.75, respectively, regardless of the smaller π‐conjugation size in C30 and C40 than in C36 and C60 . Larger γzzzz values were obtained for other fullerenes that had intermediate diradical character, in accordance with our previous valence configuration interaction (VCI) results for the two‐site diradical model. The γzzzz density analysis shows that the large positive contributions originate from the large γzzzz density distributions on the right‐ and left‐extended edges of the fullerenes, between which significant spin polarizations (related to their intermediate diradical character) appear within the spin‐unrestricted DFT level of theory. 相似文献
15.
The effects of substituents on the structure, character, and nonlinear optical (NLO) properties of the organic alkalide Li+(calix[4]pyrrole)Li? were studied by density functional theory. Natural bond orbital analysis and vertical ionization energies reveal that electron‐donating substituents strengthen the alkalide character of Li+(calix[4]pyrrole)Li? and that they are beneficial for a larger first hyperpolarizability (β0) value. However, electron‐withdrawing substituents have the opposite effect. The dependence of the NLO properties on the number of substituents and their relative position was detected in multisubstituted Li+(calix[4]pyrrole)Li? compounds. For both the amino‐ and methyl‐substituted derivatives, the polarizabilities and the first hyperpolarizabilities increase as more pyrrole β‐H atoms are substituted. Moreover, distribution of the substituents so that they are as far away from each other as possible resulted in an increase in the β0 value. The new knowledge obtained in this study may provide an effective approach to enhance the NLO responses of alkalides by employing pyrrole derivatives as complexants. 相似文献
16.
Sávio Fonseca Neidy S. S. dos Santos Prof. Dr. Antonio R. da Cunha Prof. Dr. Sylvio Canuto Prof. Dr. Patricio F. Provasi Prof. Dr. Tarciso Andrade-Filho Prof. Dr. Rodrigo Gester 《Chemphyschem》2023,24(12):e202300060
The solute polarization due to solvent is a an electrostatic quantum effect that impacts diverse molecular properties, including the nonlinear optical response of a material. An iterative procedure that allows updating the solute charge distribution in the presence of the solvent is combined with a sequential Monte Carlo/Quantum Mechanics methodology and Density Functional Theory methods to evaluate the nonlinear optical (NLO) response using the hyper Rayleigh scattering (HRS) of a series of chromones recently identified in Chamaecrista diphylla, an herbaceous plant abundant throughout the Americas and used in folk medicine. From this study, it is determined that from gas to solvent environment, the systems acquire low refractive index (n) and an improvement of the first hyperpolarizability (βHRS), signaling potential NLO uses. It is shown that the octupolar contributions (βJ=3) superate the dipolar ones (βJ=1) and dominate the second-order optical response in both gas and liquid phases, which indicate nontrivial optical materials. Moreover, the solvent environment and structural changes in the periphery can tune significantly the dipolar/octupolar balance, showing a key to control the decoupling between these contributions. 相似文献
17.
Alessandro Abbotto Prof. Dr. Luca Beverina Dr. Norberto Manfredi Dr. Giorgio A. Pagani Prof. Dr. Graziano Archetti Dr. Hans‐Georg Kuball Prof. Dr. Christian Wittenburg Dr. Jürgen Heck Prof. Dr. Jan Holtmann 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(25):6175-6185
Donor1+donor2→acceptor : The second‐order NLO molecular properties of a class of dipolar chromophores that incorporate the following design elements are investigated: 1) a substituted hydrazono moiety as a strong donor; 2) a pyrrole ring as an auxiliary donor; 3) strong acceptor groups (see figure). Their first hyperpolarisabilities show good promise for use in electro‐optical devices.
18.
Yi Huang Le Gao HaoHai Yu Prof. Zhihua Yang Prof. Junjie Li Prof. Shilie Pan 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(21):6538-6544
Four sodium-based ternary IR nonlinear optical (NLO) materials, Na6MQ4 (M=Zn, Cd; Q=S, Se), were prepared through a high-temperature flux method. The crystal structure of the compounds is built up of isolated [MQ4] tetrahedra and a 3D framework formed by the NaQn (n=4, 5) units. The two selenides, Na6MSe4 (M=Zn, Cd), as promising IR NLO materials, show moderate second-harmonic generation (SHG) responses (0.9 and 0.5×AgGaS2) with good phase-matching behavior, as well as high laser damage thresholds (2 and 1.9×AgGaS2). The two sulfides, Na6MS4 (M=Zn, Cd), exhibit higher laser damage thresholds (13 and 4×AgGaS2), but smaller SHG responses (0.3 and 0.2×AgGaS2). Theoretical calculations and statistical analyses indicate that the SHG effect and band gap in the compounds originate mainly from the distorted NaQ4 NLO-active units with a short Na−S bond length, which provides a new insight into the design of novel IR NLO materials. 相似文献
19.
Theoretical Study of the Substituent Effects on the Nonlinear Optical Properties of a Room‐Temperature‐Stable Organic Electride 下载免费PDF全文
Dr. Wei‐Ming Sun Xiang‐Hui Li Prof. Ying Li Dr. Bi‐Lian Ni Prof. Jing‐Hua Chen Prof. Chun‐Yan Li Prof. Di Wu Prof. Zhi‐Ru Li 《Chemphyschem》2016,17(23):3907-3915
Excess‐electron compounds can be considered as novel candidates for nonlinear optical (NLO) materials because of their large static first hyperpolarizabilities (β0). A room‐temperature‐stable, excess‐electron compound, that is, the organic electride Na@(TriPip222), was successfully synthesized by the Dye group (J. Am. Chem. Soc. 2005 , 127, 12416). In this work, the β0 of this electride was first evaluated to be 1.13×106 au, which revealed its potential as a high‐performance NLO material. In particular, the substituent effects of different substituents on the structure, electride character, and NLO response of this electride were systemically studied for the first time by density functional theory calculations. The results revealed that the β0 of Na@(TriPip222) could be further increased to 8.30×106 au by introducing a fluoro substituent, whereas its NLO response completely disappeared if one nitryl group was introduced because the nitro‐group substitution deprived the material of its electride identity. Moreover, herein the dependence of the NLO properties on the number of substituents and their relative positions was also detected in multifluoro‐substituted Na@(TriPip222) compounds. 相似文献
20.
The linear and nonlinear optical polarizabilities of donor-acceptor (D-pi-A) chromophores in confined geometries of calix[4]arenes are investigated through a model for interacting polar-polarizable molecules. Both the linear polarizability (alpha) and the first hyperpolarizability (beta) decrease with increasing the interdipolar angle, as expected in the oriented-gas picture. However, within the polar-polarizable model we predict deviations from the additive result, irrespective of the interdipolar angle. Depending on the nature of the chromophore, electrostatic intermolecular interactions between polar and polarizable chromophores lead to cooperative damping or enhancement of the optical responses. Specifically, for chromophores whose ground state is dominated by the neutral D-pi-A structure both alpha and beta are suppressed with respect to the prediction of the oriented-gas model, whereas the opposite holds true for chromophores whose ground state is dominated by the zwitterionic D(+)-pi-A(-). These results explain recent experimental data on a calix[4]arene functionalized with a donor-acceptor dye for nonlinear optical applications. Density functional theory calculations on the relevant crystal structure further support our interpretation. 相似文献