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UV-Vis Spectrum and the Third-order Nonlinear Optical Properties of the Chiral Camphorderived β-diketonate Platinum Complexes 被引量:1
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作者 龚雪 卫航 +1 位作者 骆开均 李权 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2014年第3期422-428,共7页
UV-Vis spectrum and the third-order nonlinear optical properties of the chiral camphor-derived β-diketonate have been studied at the B3LYP/6-31G* level. The results showed that the introduction of electron-drawing g... UV-Vis spectrum and the third-order nonlinear optical properties of the chiral camphor-derived β-diketonate have been studied at the B3LYP/6-31G* level. The results showed that the introduction of electron-drawing group -CF3 and -C3F7 on β-diketonate made the strongest absorption peak red-shift and the lowest energy absorption blue-shied. Introduction of -OC2H5 on the benzene or pyridine ring made the lowest energy absorption blue-shift. When the -C2H3 was introduced on the benzene or pyridine ring, the lowest energy absorption was red-shifted. Introduction of electron-donating group on β-diketonate can enlarge their nonlinear optical properties. On the contrary, the introduction of electron-drawing group dropped it down. 展开更多
关键词 camphor-derived β-diketonate platinum complexes the third-order nonlinear optical properties uv-vis absorption spectrum density functional theory
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Three New Coordination Polymers Constructed by Adjusting the Angles of Pyridyl or Imidazolyl-based Synthons: Structures and Solid UV-vis Properties
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作者 周春辉 周杰 +2 位作者 胡振原 金矿 胡劲松 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2016年第8期1245-1252,共8页
Three new 2D metal-organic frameworks, [M(BIDPE)2(bdc)2]n(M = Co for 1, Ni for 2) and [Ni(PIDPE)2(H2O)2(bdc)]n(3)(BIDPE = 4,4A-bis(imidazol-1-yl) diphenyl ether, PIDPE =4-(pyridyl)-4A-(imidazol-1-y... Three new 2D metal-organic frameworks, [M(BIDPE)2(bdc)2]n(M = Co for 1, Ni for 2) and [Ni(PIDPE)2(H2O)2(bdc)]n(3)(BIDPE = 4,4A-bis(imidazol-1-yl) diphenyl ether, PIDPE =4-(pyridyl)-4A-(imidazol-1-yl) diphenyl ether, bdc2- = 1,3-benzenedicarboxylate), were characterized by single-crystal X-ray diffraction, elemental analysis, PXRD, IR spectroscopy and TGA analysis.Complex 1 crystallizes in monoclinic, space group P21/n, with a = 9.1568(12), b = 16.943(2), c =15.441(2) A, β = 104.049(2)°, V = 2323.9(5) A^3, Dc = 1.420 g/cm^3, Mr = 993.83, F(000) = 1026, μ =0.440 mm-(-1) and Z = 2. Complex 2 crystallizes in monoclinic, space group P21/n, with a =9.1395(17), b = 17.019(3), c = 15.473(3) A, β = 104.651(2)°, V = 2328.5(7) A^3, Dc = 1.414 g/cm^3,Mr = 991.58, F(000) = 1024, μ = 0.487 mm^-1, Z = 2. Complex 3 also belongs to the monoclinic system, space group P21/n, with a = 11.4365(16), b = 18.346(3), c = 11.7068(17) A, β = 91.022(2)°,V = 2455.9(6) A3, Dc = 1.422 g/cm^3, Mr = 1051.66, F(000) = 1092, μ = 0.468 mm^-1, Z = 2. All complexes 1, 2 and 3 are 2D layer structures constructed from intermolecular hydrogen bonds. In addition, the solid UV-vis properties of complexes 1, 2 and 3 were also studied. 展开更多
关键词 metal-organic frameworks intermolecular hydrogen bonds solid uv-vis spectrum
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Crystal Structure and Spectrum Character of Bis[1-(4-Methoxyphenyl)-3-(1H-1,2,4-Triazol-1-yl)-1-Propanone] dichorozinc(Ⅱ) Complex
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作者 曹克广 王忠卫 +1 位作者 孙成辉 赵信岐 《Journal of Beijing Institute of Technology》 EI CAS 2005年第4期425-428,共4页
The titled new complex was synthesized and determined by X-ray diffraction. The crystal belongs to monoclinic, P-I group, a=1.8997(4)nm, b-0.581 07(12)nm, c=2.4209(5)nm, β-90.65(3)°, V=2.672 2(9) nm^3,... The titled new complex was synthesized and determined by X-ray diffraction. The crystal belongs to monoclinic, P-I group, a=1.8997(4)nm, b-0.581 07(12)nm, c=2.4209(5)nm, β-90.65(3)°, V=2.672 2(9) nm^3, Z=4, Dc= 1.488 g/cm^3, It has C2 symmetry with the axis through the Zn atom, and the zinc atom is coordinated by two N atoms of the 1-(4-methoxyphenyl) 3-( 1H-1, 2, 4-triazol-1-yl)-1-propanone ligands and two C1^- atoms, forming a slightly distorted tetrahedron. Intermolecular hydrogen bonds make the complex stable. IR and electronic spectra study of the target complex were also carried. 展开更多
关键词 1H-1 2 4-triazol-1-yl COMPLEX crystal structure uv-vis spectrum
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溶胶-凝胶法制备Al^3+掺杂ZnO薄膜的结构和光学性能 被引量:3
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作者 宋立媛 唐利斌 +5 位作者 姬荣斌 陈雪梅 刘新近 庄继胜 王茺 杨宇 《红外技术》 CSCD 北大核心 2011年第2期80-84,共5页
采用无机盐溶胶-凝胶方法在载玻片衬底上制备了ZnO:Al薄膜,利用X射线衍射(XRD)、紫外-可见光透射光谱(UV-Vis transmittance spectrum)和扫描电镜(SEM)研究了退火温度和Al3+掺杂浓度对ZnO:Al薄膜结构和光学性能的影响。结果表明,随退火... 采用无机盐溶胶-凝胶方法在载玻片衬底上制备了ZnO:Al薄膜,利用X射线衍射(XRD)、紫外-可见光透射光谱(UV-Vis transmittance spectrum)和扫描电镜(SEM)研究了退火温度和Al3+掺杂浓度对ZnO:Al薄膜结构和光学性能的影响。结果表明,随退火温度的升高或进行适当浓度的Al3+掺杂,可使(002)衍射峰的强度增强,晶粒尺寸增大,半高宽减小,薄膜的结晶质量明显改善,且可见光透过率高。 展开更多
关键词 ZnO:A1薄膜 紫外-可见光透射光谱(uv-vis TRANSMITTANCE spectrum) 扫描电镜(SEM)
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Synthesis and photochemical properties of two ICT compounds with naphthalimide and diarylamine units
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作者 蒋伟 唐霁楠 +2 位作者 孙岳明 徐文连 王华林 《Journal of Southeast University(English Edition)》 EI CAS 2008年第2期243-246,共4页
Two new diarylamine-substituted 1, 8-naphthalimide derivatives are synthesized by Cu I/18-crown-6/K2CO3 catalyst system and characterized by Fourier transform infrared (FT- IR), ^1H-NMR and elemental analyses. The U... Two new diarylamine-substituted 1, 8-naphthalimide derivatives are synthesized by Cu I/18-crown-6/K2CO3 catalyst system and characterized by Fourier transform infrared (FT- IR), ^1H-NMR and elemental analyses. The UV-vis absorption and photoluminescent (PL)spectra of the systems in n-hexane, tetrahydrofuran(THF), and CH2Cl2 are investigated. These naphthalimide molecules have an absorption band centered at about 450 nm, which is assigned to an intramolecular chargetransfer (ICT)transition, and they emit light at 492, 501 nm in a nonpolar solvent such as n-hexane, and at 600, 620 nm in a polar solvent such as CH2Cl2. From the Lippert-Mataga equation, the difference of the dipole moment between the excited state and the ground state is estimated to be 9.2 and 9.8 D for 4- ( diphenylamine )-N-( 2-methoxyphenyl )-1, 8-naphthalimide ( DMN-1 ) and 4-( 2-naphthylphenylamine )-N-( 2- methoxyphenyl)-1, 8-naphthalimide (DMN-2), respectively. This large change in the dipole moment upon excitation is typical for photoinduced ICT processes. 展开更多
关键词 NAPHTHALIMIDE diarylamine PHOTOLUMINESCENCE uv-vis spectrum intramolecular charge transfer
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Online recognition of drainage type based on UV-vis spectra and derivative neural network algorithm 被引量:4
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作者 Qiyun Zhu April Gu +3 位作者 Dan Li Tianmu Zhang Lunhong Xiang Miao He 《Frontiers of Environmental Science & Engineering》 SCIE EI CSCD 2021年第6期447-455,共9页
Optimizing sewage collection is important for water pollution control and wastewater treatment plants quality and efficiency improvement.Currently,the urban drainage pipeline network is upgrading to improve its classi... Optimizing sewage collection is important for water pollution control and wastewater treatment plants quality and efficiency improvement.Currently,the urban drainage pipeline network is upgrading to improve its classification and collection ability.However,there is a lack of efficient online monitoring and identification technology.UV-visible absorption spectrum probe is considered as a potential monitoring method due to its small size,reagent-free and fast detection.Because the performance parameters of probe like optic resolution,dynamic interval and signal-to-noise ratio are weak and high turbidity of sewage raises the noise level,it is necessary to extract shape features from the turbidity disturbed drainage spectrum for classification purposes.In this study,drainage network samples were online collected and tested,and four types were labeled according to sample sites and environment situation.Derivative spectrum were adopted to amplify the shape features,while convolutional neural network algorithm was established to conduct nonlinear spectrum classification.Influence of input and network structure on classification accuracy was compared.Original spectrum,first-order derivative spectrum and a combination of both were set to be three different inputs.Artificial neural network with or without convolutional layer were set be two different network structures.The results revealed a convolutional neural network combined with inputs of first and zero-order derivatives was proposed to have the best classification effect on domestic sewage,mixed rainwater,rainwater and industrial sewage.The recognition rate of industrial wastewater was 100%,and the recognition rate of domestic sewage and rainwater mixing system were over 90%. 展开更多
关键词 Drainage online recognition uv-vis spectra Derivative spectrum Convolutional neural network
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Monitoring the hydrolyzation of aspirin during the dissolution testing for aspirin delayed-release tablets with a fiber-optic dissolution system 被引量:4
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作者 Yan Wang Ping-Ping Xu +4 位作者 Xin-Xia Li Kun Nie Ming-Fu Tuo Bin Kong Jian Chen 《Journal of Pharmaceutical Analysis》 CAS 2012年第5期386-389,共4页
The purpose of this study was to investigate the hydrolyzation of aspirin during the process of dissolution testing for aspirin delayed-release tablets. Hydrolysis product of salicylic acid can result in adverse effec... The purpose of this study was to investigate the hydrolyzation of aspirin during the process of dissolution testing for aspirin delayed-release tablets. Hydrolysis product of salicylic acid can result in adverse effects and affect the determination of dissolution rate assaying. In this study, the technique of differential spectra was employed, which made it possible to monitor the dissolution testing in situ. The results showed that the hydrolyzation of aspirin made the percentage of salicylic acid exceed the limit of free salicylic acid (4.0), and the hydrolyzation may affect the quality detection of aspirin delayed-release tablets. 展开更多
关键词 Aspirin delayed-releasetablets Drug dissolution test Fiber-optic dissolution system uv-vis spectrum
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Electronic Structure and Physical Characteristics of Dioxin Under External Electric Field 被引量:2
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作者 Wenyi Yin Xiangyun Zhang +4 位作者 Bumaliya Abulimiti Yuzhu Liu Yihui Yan Fengbin Zhou Feng Jin 《Computers, Materials & Continua》 SCIE EI 2018年第4期165-176,共12页
Dioxin is a highly toxic and caustic substance,which widely existed in the atmosphere,soil and water with tiny particles.Dioxin pollution has become a major problem that concerns the survival of mankind,which must be ... Dioxin is a highly toxic and caustic substance,which widely existed in the atmosphere,soil and water with tiny particles.Dioxin pollution has become a major problem that concerns the survival of mankind,which must be strictly controlled.The bond length,bond angle,energy,dipole moment,orbital energy level distribution of dioxin under the external field are investigated using DFT(density functional theory)on basis set level of B3LYP/6-31G(d,p).The results indicate that with the increase of the electric field,the length of one Carbon-Oxygen bond increases while another Carbon-Oxygen bond decreases.The energy gradually decreases with the electric field,while the change of the dipole moment has an opposite trend.In the infrared spectra,the vibration frequency decreases with the electric field increasing and shows an obvious red shift.Moreover,the ultraviolet-visible absorption spectra under different electric fields are analyzed with TD-DFT(time-dependent density functional theory)method.The wavelength of the strongest absorption peak increases and occurs red shift with the increase of the electric field.All the above results can provide reference for further research on the properties of dioxin under different external electric field. 展开更多
关键词 DIOXIN IR spectrum uv-vis spectrum electric field density functional theory excited states
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Surface-enhanced Raman Scattering from Molecules Adsorbed on Mixed Silver/Gold Nanoparticle Surfaces 被引量:1
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作者 FANGJing-huai HUANGYun-xia +1 位作者 LIXia DOUXiao-ming 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2004年第6期817-820,共4页
关键词 Silver nanoparticle Gold nanoparticle uv-vis spectrum SERS
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Construction of J- and H- Aggregates of meso-Tetrakis (4-hydroxyphenyl) porphyrin Diacid (H_4THPP^(2+)) 被引量:1
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作者 YingHuiZHANG YangWU 《Chinese Chemical Letters》 SCIE CAS CSCD 2005年第2期279-281,共3页
UV-Vis spectrum was utilized to study the aggregation behaviors of H4THPP2+ inDMF-chloroform mixture and water. It was found that J-aggregation of H4THPP2+ was formed inDMF-chloroform mixture and H-aggregate was forme... UV-Vis spectrum was utilized to study the aggregation behaviors of H4THPP2+ inDMF-chloroform mixture and water. It was found that J-aggregation of H4THPP2+ was formed inDMF-chloroform mixture and H-aggregate was formed in aqueous solution with highionic-strength, as indicated by different spectral characteristics of different H4THPP2+ aggregates. 展开更多
关键词 H4THPP2+ AGGREGATION uv-vis spectrum.
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Synthesis and Spectral Characteristics for Zinc Tetraphenylporphyrin Modified Zinc Oxide Nanowires
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作者 HUANG Hui-han KE Jian-xi +1 位作者 XIE Wen-qiang PAN Hai-bo 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2016年第S1期427-428,共2页
A nest-like architectures(ZnO NAs)were prepared onto the conductive glass(ITO)by hydrothermal method.A metal-free porphyrin,tetraphenylporphyrin(H2TPP),was synthesized via Adler method.Zn ions with Zn-unsaturated coor... A nest-like architectures(ZnO NAs)were prepared onto the conductive glass(ITO)by hydrothermal method.A metal-free porphyrin,tetraphenylporphyrin(H2TPP),was synthesized via Adler method.Zn ions with Zn-unsaturated coordination bonds on the surface of ZnO NAs were used as a template,and also H2TPP was used as"molecular fragments".Zinc tetraphenylporphyrin(ZnTPP)molecules were obtained on the surface of ZnO NAs by in-situ method.ZnO NAs direct provides of zinc source makes ZnTPP stably coated on the surface of ZnO NAs nanosheet,formed a tight composite materials(ZnTPP/ZnO NAs).Due toZnTPP with four phenyls in meso position,the surface of ZnTPP/ZnO NAs was with hydrophobic property.In the photocatalytic experiment,the degradation selectivity for phenol(hydrophobicity)in the mixture of phenol and rhodamine B(hydrophily)was increased under visible irradiation. 展开更多
关键词 ZNO IN-SITU Zinc tetraphenylporphyrin uv-vis spectrum Selective photocatalysis
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Synthesis and Spectroscopic Properties of a Series of New tetra-Substituted Metal Phthalocyanines
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作者 YU Hai-ling YANG Jin, FU Qiang MA Ji-cheng LI Wei-li 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2008年第2期123-128,共6页
A new class of metal phthalocyanines(MPcs) containing four 8-quinolinol(8-QH) derivative moieties were successfully synthesized and characterized by mass spectroscopy, IR, UV-Vis and element analysis, the results ... A new class of metal phthalocyanines(MPcs) containing four 8-quinolinol(8-QH) derivative moieties were successfully synthesized and characterized by mass spectroscopy, IR, UV-Vis and element analysis, the results of which were consistent with the proposed structures. All of them can dissolve in common organic solvents, such as dichloromethane, chloroform, and acetone. The effect of metal ion on the absorption of Q band was studied with UV-Vis spectra. The fluorescent properties for those complexes were also investigated. 展开更多
关键词 Metal phthalocyanines SOLUBLE 8-Quinolinol uv-vis spectrum
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Synthesis,Crystal Structure and Photoluminescence of Ethyl Coumarin-3-carboxylate Derivatives
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作者 宋立美 高建华 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2014年第1期57-64,共8页
The ethyl coumarin-3-carboxylate (1) and its two derivatives, ethyl 7-methoxy-2- oxo-2H-chromene-3-carboxylate (2) and ethyl 7-(3-methylbut-2-enyloxy)-2-oxo-2H-chromene-3- carboxylate(3), were synthesized, cha... The ethyl coumarin-3-carboxylate (1) and its two derivatives, ethyl 7-methoxy-2- oxo-2H-chromene-3-carboxylate (2) and ethyl 7-(3-methylbut-2-enyloxy)-2-oxo-2H-chromene-3- carboxylate(3), were synthesized, characterized and their UV-vis spectra and photoluminescence were investigated. Compound 2 crystallizes in the monoclinic system with space group C2/c, a = 25.884(4), b = 6.8365(11), c = 13.816(2) A, β = 104.876(2)°, V= 2362.9(7) A3, Z = 8, Dc= 1.396 g/cm3, Mr. = 248.23, F(000) = 1040 and g = 0.108 mm-1. Compound 3 crystallizes in the monoclinic system with space group P21/c, a = 15.685(6), b = 8.373(3), c = i3.063(5) A, β = 111.862(6)°, V= 1592.2(10) A3, Z = 4, Dc = 1.261 g/cm3, M,.= 302.31, F(000) = 640 and p = 0.093 mm^-1. Both the absorption and emission of the two derivatives were stronger than that of ethyl coumarin-3-carboxylate due to the larger conjugation of their electron donor group moiety at the 7-position. Under ultraviolet light excitation, the two derivatives exhibit strong blue-violet emission. 展开更多
关键词 coumarin derivatives crystal structure uv-vis spectrum PHOTOLUMINESCENCE
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Different J-Type Aggregates of meso-Tetrakis (4-hydroxyphenyl) porphyrin (H_(2)THPP) Formed in Different Solvents
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作者 YingHuiZHANG YangWU 《Chinese Chemical Letters》 SCIE CAS CSCD 2005年第4期534-536,共3页
The aggregation of meso-tetrakis(4-hydroxyphenyl)porphyrin (H2THPP) in dimethyl- formamide (DMF)-water solution and in DMF-chloroform solution was studied by UV-vis absorption spectroscopy. The red shift of Soret ba... The aggregation of meso-tetrakis(4-hydroxyphenyl)porphyrin (H2THPP) in dimethyl- formamide (DMF)-water solution and in DMF-chloroform solution was studied by UV-vis absorption spectroscopy. The red shift of Soret band indicates the formation of J-type aggregates of H2THPP in these two solutions. However, different shift extent of Soret band, 12 nm in DMF-water solution and 32 nm in DMF-chloroform solution, implies structural difference between these two J-type aggregates. The hydrogen bond between hydroxyl group and N-H bonds in porphyrin ring is thought as the main cause to the formation of J-type aggregate in DMF- chloroform solution, whereas the π?σ interaction between two adjacent porphyrin cores is thought as the main cause of the formation of J-type aggregate in DMF-water solution 展开更多
关键词 H2THPP AGGREGATION uv-vis absorption spectrum.
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Construction of a 3D Co(Ⅱ) Framework Based on Two Types of V-shaped Bidentate Ligands
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作者 胡劲松 张雷 +2 位作者 石建军 邢宏龙 何杰 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2014年第4期579-584,共6页
A three-dimensional (3D) coordination polymer {[Co(bdc)(dpb)]·H2O}n (1) was prepared by solvothermal reaction of 1,3-dipyridyl benzene (dpb) with deprotonated 1,3-benzene- dicarboxylate (H2bdc), and w... A three-dimensional (3D) coordination polymer {[Co(bdc)(dpb)]·H2O}n (1) was prepared by solvothermal reaction of 1,3-dipyridyl benzene (dpb) with deprotonated 1,3-benzene- dicarboxylate (H2bdc), and was characterized by elemental analysis, IR spectroscopy, and X-ray single-crystal diffraction. It crystallizes in the monoclinic system, space group C2/c with α = 15.478(6), b = 12.865(5), c = 24.091(10) ?, β = 95.599(5)°, V = 4774(3) ?3, C24H18CoN2O5, Mr = 473.34, Dc = 1.267 g/cm3, F(000) = 1864.0, μ = 0.748 mm-1 and Z = 8. Each Co(II) ion links three bdc2- anions to form an infinitely 1D ladder-shaped chain containing binuclear [(COO)Co]2 cluster, and dpb links adjacent 1D chains to form a 3D pcu framework. In addition, the UV-vis of 1 was also studied. 展开更多
关键词 coordination polymer V-shaped ligand CRYSTAL STRUCTURE uv-vis spectrum
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Ligand-controlled First Hyperpolarizabilities of a Series of Tetrahedral Iridium Clusters Ir_4(CO)_9L: a TDDFT Study
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作者 李福君 洒荣建 吴克琛 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2009年第1期106-112,共7页
A series of tetrahedral iridium carbonyl clusters coordinated by systematically varied series of ligands have been studied by TDDFT method focusing on their electronic and non- linear optical properties. The clusters ... A series of tetrahedral iridium carbonyl clusters coordinated by systematically varied series of ligands have been studied by TDDFT method focusing on their electronic and non- linear optical properties. The clusters of Ir4(CO)12 (1), Ir4(μ-CO)3(CO)9 (2), Ir4(μ-L)(CO)10 (L = dppm 3, dppe 4, (Ph2P)2CHMe 5, Ph2P(CH2)3PPh2 6) and Ir4(CO)10(phen) (phen = 1,10-phen- anthroline) (7) exhibit the first static hyperpolarizabilities of medium magnitude (βtot-10×10^-30 esu). The second order nonlinear optical response of the seven clusters increase from 0 to 23 ×10^-30 esu; the high symmetric cluster Ir4(CO)12 debases its symmetry and presents the second order nonlinear optical behavior as the coordination style of some carbonyls changes to bridge style, and then the response increases regularly with the systematical variation of the ligands. The origination of the first hyperpolarizability is discussed by the expanded orbital decomposition scheme. The results suggest the d-d electron transition from the apical iridium atom to the other three Ir atoms inside the metal skeleton, and d-πelectron transitions from metals to carbonyls are responsible for the first hyperpolarizabilities. Particularly, for cluster 7, the charge transfer from d orbitals of iridium to π* orbirals of phenanthroline originates the first hyperpolarizabilities. 展开更多
关键词 TDDFT uv-vis spectrum iridium duster nonlinear optical
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TDDFT Study on the Electronic Excitations and First Hyperpolarizabilities of Mixed-metal Carbonyl Clusters W_2Ir_2(μ-L)(CO)_8(η~5-C_5H_4Me)_2(L=dppe/dppf)
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作者 李福君 洒荣建 吴克琛 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2009年第1期99-105,共7页
Mixed-metal carbonyl clusters of W2Ir2(CO)10(η^5-C5H4Me)2 1 and W2Ir2(μ-L)(CO)8(η^5-C5H4Me)2 (L = dppe 2, dppf 3) have been studied by TDDFT method focusing on their electronic and nonlinear optical pro... Mixed-metal carbonyl clusters of W2Ir2(CO)10(η^5-C5H4Me)2 1 and W2Ir2(μ-L)(CO)8(η^5-C5H4Me)2 (L = dppe 2, dppf 3) have been studied by TDDFT method focusing on their electronic and nonlinear optical properties. These three clusters exhibit the first static hyperpolarizabilities of medium magnitude (βtot-10×10^-30 esu). The origin of β is discussed by the new proposed orbital-pair decomposition scheme by Barandes et al. The result suggests that the β values of the two clusters are mainly originated from d-d electron transition within the metal skeleton, and d-p (π*) electron transition from metals to carbonyls and phenyl. The additional coordination by the electron donor group, ferrocene, makes cluster 3 own much larger β values, and the relatively longer range charge transfer from d orbitals of ferrocene to d orbirals of Ir and W is responsible for the enhanced β values. 展开更多
关键词 TDDFT uv-vis spectrum transition metal nonlinear optical
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Development of an Analytical Method for Evaluating the Catalytic Active Sites of Titanium Silicalite Zeolite
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作者 Xiaoyan Huang Yan Xue +3 位作者 Xin Gao Baojun Li Yiqiang Wen Xiangyu Wang 《Journal of Materials Science and Chemical Engineering》 2015年第6期1-6,共6页
A simple, quick, sensitive, accurate and precise method has been developed for evaluating the catalytic active sites of titanium silicalite-1 (TS-1). The catalytic active sites of titanium silicalite zeolite depend on... A simple, quick, sensitive, accurate and precise method has been developed for evaluating the catalytic active sites of titanium silicalite-1 (TS-1). The catalytic active sites of titanium silicalite zeolite depend on the effectively active species (EAS) in TS-1 which react with specific substrates quickly. However, the EAS was hard to be evaluated with conventional instruments and techniques in the past. In this paper, the EAS was formed in TS-1 upon interaction with H2O2, and its presence could be confirmed by UV-vis spectroscopy which has an absorption peak at 385 nm. The absorbance at 385 nm was found to be linearly related to time, and when the absorbance and the increasing rate of absorbance (k) increased, the catalytic performance of TS-1 enhanced. 展开更多
关键词 Effectively Active Species (EAS) Titanium SILICALITE ZEOLITE uv-vis spectrum ABSORBANCE
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Effect of Conformation on UV-Vis Absorption Spectra of Disazo Reactive Red Dyes
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作者 XIE Xiaomei LI Xiaolei +2 位作者 LUO Hanhan LEI Kelin LI Wei 《Wuhan University Journal of Natural Sciences》 CAS CSCD 2016年第6期512-518,共7页
In this study,twenty disazo reactive red dyes with J acid as coupling components were selected,and their ground state geometry were studied with BLYP functional and TZVP basis set. The UV-vis absorption spectra were c... In this study,twenty disazo reactive red dyes with J acid as coupling components were selected,and their ground state geometry were studied with BLYP functional and TZVP basis set. The UV-vis absorption spectra were calculated by time-dependent density functional theory(TDDFT) employing B3 LYP and PBE0 hybrid functionals and TZVP basis set,and the absolute mean errors are 0.094 e V and 0.133 e V for B3 LYP and PBE0,respectively. From the comparison of the calculated λ_(max) of the three conformations of disazo reactive red dye,cis-,trans-,and azo,with that of experimental one,we find out that conformation plays an important role on UV-Vis absorption. Dyes 6 and 8 exist in azo conformation rather than in cis-conformation. "Hole-electron" distribution analysis reveals that although these λ_(max) arises from different electron transitions,these electron excitations have the same character of local excitation(LE). 展开更多
关键词 dye uv-vis absorption spectrum time-dependent density functional theory(TDDFT)
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Synthesis and anion recognition of neutral receptors based on multiamide calix[4]arene 被引量:2
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作者 LIU Shunying WANG Fajun WEI Lanhua XIAO Wang MENG Lingzhi HE Yongbing 《Science China Chemistry》 SCIE EI CAS 2004年第2期145-151,共7页
Two multiamide calix[4]arenes (5, 6) were synthesized and characterized by NMR, MS and elemental analysis. The binding properties of receptors with some anions (π-O2NPhOPO 3 2? , π-O2NPhO?, H2PO 4 ? , Ac?, Cl?, Br? ... Two multiamide calix[4]arenes (5, 6) were synthesized and characterized by NMR, MS and elemental analysis. The binding properties of receptors with some anions (π-O2NPhOPO 3 2? , π-O2NPhO?, H2PO 4 ? , Ac?, Cl?, Br? and I?) were studied by UV-Vis spectra. The results indicate that the tetraamide calix[4]arenes (5, 6) have a good selectivity to the anions containing aromatic ring (π-O2NPhOPO3 2?, π-O2NPhO?). The 1 : 1 complexes between host and guest were formed through multiple hydrogen bonding and π-π interactions. The hosts 5 and 6 also show a definite binding ability for the anions (H2PO 4 ? , Ac?, Cl?) that have no ultraviolet absorption, which provides a simple method of spectrum detection for these anions. 展开更多
关键词 multiple AMIDE arene NEUTRAL ANION receptor synthesis ANION recognition uv-vis spectrum.
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