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1.
Introduction Copper(I) complexes have received much attention for their being less expensive and environmentally friendly, various coordination geometry, rich photo-chemical and photophysical properties.1-7 It is well known that copper complexes with diimine (2,2'-bipy- ridine, 1,10-phenanthroline and their substituted deriva-tives designated as diimine) generally exhibit low en-ergy metal-to-ligand charge-transfer (MLCT) states lo-cated in the regions of 350650 nm (e ≈ 103—104 dm3昺ol-1昪…  相似文献   

2.
Two-photon absorption (TPA) is a process in which two photons are simultaneously absorbed to an excited state via a virtual state. The synthesis of organic optical materials with large TPA cross section has become a subject of great interest in recent years due to various application such as three-dimensional fluorescence imaging1, optical data storage2,3 and lithographic microfabrication4-6. Recently we have synthesized a new organic dye DEAHAS that is a symmetrically substituted stilbe…  相似文献   

3.
By hydrothermal synthesis,a manganese(Ⅱ)tetracarboxylate [Mn(2,2'-bipyridi-ne)btec)o.5(H2O)]2n(H4btec=1,2,4,5-benzenetetracarboxylic acid)was obtained and characteri-zed by single-crystal X-ray diffraction,IR,elemental analysis and thermogravimetrie analysis.It crystallizes in triclinic,space group P(1),with a=7.721(4),b=8.905(5),c=10.712(6)(A),α=80.899(8),β=70.371(8),γ=78.201(8)°,z=2,V=675.8(7)(A)3,Mr=354.20,Dc=1.741 g/cm3,μ=1.007mm-1,F(000)=360,S=0.956,(△/σ)max=0.000,the final R=0.0490 and wR=0.1262.This compound presents an infinite 1D polymer featuring a double-chain structure.The Mn(Ⅱ)ion is five-coordinated.The four carboxylate groups of btec4- are all deprotonated and coordinated to four Mn atoms in a monodentate fashion,forming a 1D double chain structure with a cavity.Such chains are interconnected by π-π stacking interactions into 2D layers which are further interlinked into a supramolecular structure by hydrogen bonds.  相似文献   

4.
王庆伦  廖代正  阎世平  姜宗慧  程鹏 《中国化学》2002,20(11):1249-1255
IntroductionMolecularmagnetismofpolynuclearcomplexesisofconsiderableinterestfordesigningnewmagneticmaterialsandforinvestigatingtherelationshipbetweenthestructureandtheroleofthepolymetallicactivesitesinbiologicalsystems.1 4 Journauxetal .5haverecentlyprop…  相似文献   

5.
New thermally stable poly(urethane-imide)s (PUIs) were synthesized to investigate aliphatic and aromatic group effects on various properties such as thermal stability and electrochemical properties. Thermal characterizations were carried out by TG-DTA and DSC techniques. TGA results showed that the PUIs derived from aromatic diisocyanates had relatively higher thermal stabilities as compared to the aliphatic diisocyanate. They have between 223–245°C onset temperature and above 37% char at 1000°C. Also, thermal degradation values show that PUIs have higher stability than conventional PU. DSC results showed that the new PUIs have Tg values between 134 and 138°C. Fluorescence measurements were performed using dimethyl sulfoxide solutions and also, the optimization of the concentrations maximal emission intensity was investigated in dimethyl sulfoxide. As a result, the remarkable properties related to the fluorescence and thermal measurements of the polymers were obtained. Therefore, these polymers could be used in various application fields because of the fluorescent and thermal properties.  相似文献   

6.
Two new cobalt(Ⅱ)complexes[Co_2(2,2?-bipy)_2(dpa)_2(H_2O)_5]·4H_2O(1)and Co(2,2?-bipy)_3(SO_4)]·7.5H_2O(2)have been synthesized with diaphonic acid(H_2dpa)and 2,2?-bipyridine(2,2?-bipy)as ligands.In 1,two neighboring cobalt(Ⅱ)ions are linked together by one bridging diaphonic acid group,forming an asymmetric dinuclear structure.1 crystallizes in triclinic,space group ■ with a=9.825(6),b=13.007(8),c=19.586(1)?,α=80.773(1)o,β=77.065(1)o,γ=85.902(1)o,M_r=431.4,V=2406.5(3)?~3,D_c=1.48 g/cm~3,Z=2,μ(Mo Kα)=0.767 mm~(-1),F(000)=1112,the final R=0.0379 and wR=0.0862.The central cobalt(Ⅱ)ions in 1 and 2 are coordinated with six atoms,forming distorted octahedral coordination geometry.The fluorescence and thermal stability properties of 1 and 2 are also reported.  相似文献   

7.
8.
The complexes of [Cu(bpy)(H2O)(CBA)2]n 1 and [Cu(phen)(H2O)(CBA)2]·H2O 2 based on p-cyanobenzoic acid(HCBA) have been synthesized in aqueous ethanolic solution at room temperature. The single-crystal X-ray diffraction studies demonstrated that complex 1 crystallizes in orthorhombic and complex 2 is of triclinic system. The results indicate the complex 1 shows a 1D chain structure bridged by two carboxylic oxygen atoms from CBA–, and complex 2 is a mononuclear structure. Through intermolecular hydrogen bonding and π...π stacking interactions, the complexes are assembled into supramolecular structures. Complex 1 has been characterized by magnetic measurements. The magnetic measurement indicates that weak ferromagnetic interaction(zJ= 0.038(5)) between the Cu2+ ions is dominant in the structure. The IR spectrum and results of thermal and elemental analyses are also presented.  相似文献   

9.
This paper undertakes the synthesis by slow evaporation method at room temperature of a new organic–inorganic hybrid material with the general formula [C12H13N2O]H2AsO4. The newly developed hybrid is characterized by X-ray single crystal diffraction, Infrared, Raman spectroscopy and density functional theory (DFT) calculations. At ambient temperature, this compound crystallizes in the non-centrosymmetric space group P212121 of the orthorhombic system. The structural arrangement is formed by infinite anionic chains extending parallel to the direction [100]. The organic entities are linked to these chains by N–H···O type hydrogen bonds which play an important role in the cohesion of the one-dimensional network. The optimized molecular structure, vibrational spectra and the optical properties were calculated by the DFT method using the B3LYP function with the LanL2DZ basis set. The vibrational wavenumbers were evaluated for this compound by using transferable scale factor. The first hyperpolarizability value βtot of the title compound is equal to 15.94?×?10?31 esu. Hence, the large β value calculated by the B3LYP method shows that the studied compound is a good NLO material and is suitable for future non-linear optical studies. The HOMO–LUMO energy gap and other related molecular properties are going to be discussed and reported later.  相似文献   

10.
N,N–Diphenylamidines and the silver(I) complexes of their deprotonated anions have been synthesized. Previously uncharacterized tetrameric structural motifs were produced by the inclusion of alkyl substituents at the amidinate carbon. The addition of a 2-methoxy functional group to the phenyl ring resulted in a cationic silver trimer in which hydrogen bonding links silver(I)-bound water molecules to the methoxy substituents. The thermal stabilities of the tetrameric species vary with alkyl chain length. The new complexes are: tetrakis(N,N-diphenylpropamidinato) tetra silver(I), 1, tetrakis(N,N-diphenylbutamidinato) tetrasilver(I) 2, tetrakis(N,N-diphenylpentamidinato) tetra silver(I) 3, (N,N-diphenyloctamidinato)silver(I) 4, (tetrakis(N,N-di(4-n-butyl)phenylpropamidinato)tetrasilver(I), 5, bis(N,N-di(2-methoxy)phenylacetamidinato)diaquatrisilver(I) nitrate 6 and tetrakis(N,N-di(4-methoxy)phenylacetamidinato) tetrasilver(I), 7. Compounds 1, 5, 6 and 7 were structurally characterized by X-ray methods.  相似文献   

11.
A new mercury(II) complex containing dmit ligand and biquaternary ammonium cation, DPyE[Hg(dmit)2] (1) (DPyE2+ = N,N’-ethylidenedipyridinium, dmit = 1,3-dithiol-2-thione-4,5-dithiolate), was synthesized and fully characterized by elemental analysis, IR, 1H-NMR, UV–Vis, TG, single crystal X-ray diffraction, and powder X-ray diffraction. Moreover, the electrochemical properties and conductivities of complex 1 were studied by cyclic voltammetry and four-probe AC technique, respectively. Complex 1 crystallizes in the monoclinic space group P 21/n with a = 8.1815(2) Å, b = 12.8701(5) Å, c = 23.2681(7) Å, β = 90.922(3)°, Z = 4, V = 2449.75(14) Å3, Dc = 2.114 g·cm–3. The crystal structure shows that the dihedral angle of two dmit ligands of [Hg(dmit)2]2– anion is closed to vertical, which results in the formation of a distorted HgS4 tetrahedral geometry. The S···S short contacts assemble [Hg(dmit)2]2– anions into 1D, 2D, and 3D supramolecular network. The DPyE2+ cations are located in the caves, providing additional stabilization to crystal packing via C–H···S hydrogen bonds to [Hg(dmit)2]2– anions. The crystal packing of 1 is characterized by face-to-face π-π contacts between DPyE2+ cations and [Hg(dmit)2]2– anions, which result in two orthogonally oriented and mixed stacking columns. These stacking columns interweave into a 2D network, which is further connected to a 3D network via interplanar S···S contacts. In addition, the temperature-dependent conductivity in the range of 50–300 K reveals semi-conducting properties of complex 1, and a room temperature conductivity of 1.53 × 10–3 S·cm–1 is observed.  相似文献   

12.

Three new binuclear w -oxalato copper(II) complexes of composition [(Cu(N,N' -dieten) H2O)2ox](ClO4)2 ·H2O (1) (N,N'-dieten = N,N'-diethylethylenediamine, H2ox = oxalic acid), [(Cu(trimeen)H2O)2ox](ClO4)2·2H2O (2) (trimeen = N,N,N'-trimethylethylenediamine) and [(Cu(trimeen)H2O)2ox](NO3)2 ·2H2O (3) have been isolated from the reactions of Cu(ClO4)2 ·6H2O (or Cu(NO3)2 ·3H2O), the appropriate amine and Na2ox in water and have been characterized by IR and electronic spectroscopy and magnetic measurements. The crystal structure of [(Cu(N,N' -dieten)H2O)2 ox](ClO4)2.H2O (1) has been determined by single-crystal X-ray analysis. The structure of ( 1 ) consists of binuclear cations [(N,N'-dieten)H2O)Cu(ox)Cu(N,N'-dieten)H2O)]2+, perchlorate anions and water molecules of crystallization. The copper atom is coordinated by two oxygen atoms of the oxalato ligand, two nitrogen atoms belonging to N,N'-dieten and one oxygen atom of water in a distorted square-pyramidal arrangement. The temperature dependence of magnetic susceptibilities (78-293 K) was measured for 1-3 . Magnetochemical measurements show that copper(II) ions in these compounds are antiferromagnetically coupled with J = -172 cm-1, -172 cm-1 and -168 cm-1 (H = -2JS 1 S 2, S 1= S 2 = 1/2) for 1, 2 and 3, respectively.  相似文献   

13.
Themetalmacrocycliccomplexeswiththeirunusualoxidationstateshaveattractedmuchinterest.Silver(Il)andsi1ver(IlI)compoundsareusuallyunstab1eduetotheirstrongoxidation.Butsometetraazamacrocyclicligandscandirectlygivestablecom-plexesofsiIver(Il)throughdisproportionatedreactionofsilver(I).12fIere,wereportthesynthesisandeIectrochemicalbehaviorofanewsilver(Il)com-plexAgL(CIO')2(L=5,7,l2,l4-tetraethyl-5,l2-dimethyl-l,4,8,ll-tetraazacyclotetradec-4,l1-diene).Therelativeinformationaboutothersilver(1I…  相似文献   

14.
Imidazole groups play an important role in the coordination chemistry of the metal ions in many biological systems1. Earlier work has established its suitability for formations of binuclear copper1, iron2 and manganese3 complexes. Reaction of EDTB with Cu(H2O)6(BF4)2 in absolute ethanol has given a six-coordinate complex of [Cu(EDTB)](BF4)(BF3?O(C2H5)2)H2O4. Rare earth ions have similar physical and chemical properties with Ca2+ and Mg2+ which are important in biological systems. Wan…  相似文献   

15.
A new family of boron(III) chelates is introduced whereby molecular chirality, confirmed by circular dichroism, is imported during synthesis such that isolation of the diastereoisomers does not require separation procedures. The photophysical properties of two members of the family have been examined: the N,O,O-salicylaldehyde-based derivative shows pronounced intramolecular charge-transfer character in fluid solution and is weakly fluorescent, with a large Stokes shift. The corresponding 2-methylamino-benzaldehyde-derived N,N,O-chelate absorbs and fluoresces in the visible region with a much smaller Stokes shift. Orange fluorescence is also observed for this compound as a cast film. Temperature-dependence studies show that decay of the fluorescent state is weakly activated but emission is less than quantitative at 77 K. Quite rare for boron(III)-based chelates, this derivative undergoes intersystem crossing to form a meta-stable triplet-excited state. X-ray crystal structures are reported for both compounds, along with simulated ECD spectra.  相似文献   

16.
IntroductionDye sensitizedsolarcells (DSSC)havebecomethefocusofmanyinvestigationssinceMichaelGr tzelandco workersmadethedyemoleculesadsorbedonaporousnet workoftheinterconnectednanometer sizedcrystallinesofawidebandgapsemiconductor.1 3Animpressivesolar to electricalenergyconversionefficiencyof 10 %hasbeenre portedanditmakespracticalapplicationfeasible .4 Thissystemconsistsofadye coatedsemiconductorelectrodeandacounterelectrodearrangedinasandwichconfigura tionandtheinter electrodespaceisfilled…  相似文献   

17.
IntroductionELCisatechniquebywhichachemiluminescentreactionisgeneratedfromthereagentsproducedinthevicinityofanelectrodesurfac...  相似文献   

18.
Two new mononuclear lanthanide(Ⅲ) complexes Ln(pytz)3(H2O)3·(H2O)3.5[Ln=Tb(1);Eu(2);Hpytz=5-(2-pyridyl)tetrazole] were synthesized by reacting Hpytz with the corresponding lanthanide(Ⅲ) ions and characterized.The single crystal X-ray diffraction analysis reveals that complexes 1 and 2 are isostructural and the lanthanide(Ⅲ) ions in both complexes 1 and 2 are nine-coordinated,with three oxygen atoms of three coordination water molecules and six nitrogen atoms of three pytz ligands,forming a monocapped square antiprism.Extensive hydrogen bonds exist,resulting in a three-dimensional supramolecular network structure by hydrogen-bonds in both complexes 1 and 2,respectively.Complex 1 exhibits typical green fluorescence of Tb(Ⅲ) ion and complex 2 red fluorescence of Eu(Ⅲ) ion,in solid state at room temperature.  相似文献   

19.
Two novel silver(I) complexes {[Ag(OTf)(PPh3)(4,4'-bipy)]}∞(1) and {[Ag2-(OTf)2(dppb)3](CH3CN)4}∞(2)(OTf = trifluoromethanesulfonate, PPh3 = triphenylphophine, 4,4'-bipy = 4,4'-bipyridine, dppb = bis(diphenylphosphino)butane) have been synthesized and characterized by IR, single-crystal X-ray diffraction, fluorescence spectrum and 1H NMR spectroscopy. Complex 1 crystallizes in orthorhombic, space group Pna21 with a = 19.259(2), b = 9.85070(12), c = 16.3827(17) ?, V = 3108.0(5) ?3, C29H23F3N2O3 PSAg, Mr = 675.39, Z = 4, Dc = 1.443 g/cm3, F(000) = 1360, μ = 0.816 mm-1, the final R = 0.0675 and w R = 0.1722 for 3662 observed reflections(I 2σ(I)). Complex 2 crystallizes in triclinic, space group P1 with a = 12.9370(11), b = 13.5261(13), c = 16.4539(15) ?, α = 106.7120(10), β = 97.3830(10), γ = 113.027(2)?, V = 2441.2(4)?3, C94H96F6N4O6P6S2Ag2, Mr = 1957.43, Z = 1, Dc = 1.331 g/cm3, F(000) = 1006, μ = 0.605 mm-1, the final R = 0.0717 and w R = 0.1795 for 5128 observed reflections(I 2σ(I)). Complex 1 is of zigzag chain structure, in which each Ag atom is coordinated by one OTf- anion, two N atoms from two 4,4'-bipy molecules and one P atom from PPh3 ligand. In 2, the central Ag atom is coordinated with one OTf- anion and three P atoms from three dppb ligands, which leads to the formation of a zigzag ring-bridge-ring chain with each ring consisting of two Ag atoms and two dppb ligands.  相似文献   

20.
A novel pyridinium salt, 2,4-bis[p-(N,N-dimethylamino)styryll-N-metlayl pyridinium iodide (BMSPI) was synthesized and characterized by TG, ^1H NMR spectroscopy and elemental analysis, and the reaction process was studied by using ES-MS. When BMSPI was pumped by a pulsed 1064 nm, 50 ps laser beam, it manifests highly efficient TPA (Two-Photon Absorption) and up-conversion superradiance. The up-conversion efficiency was 6.0% at the pump energy of 4-6 mJ and the lifetime of two-photon fluorescence was measured as 59 ps.  相似文献   

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