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1.
Based on the template of protonated BPDO(B PDO = 4,4'-bipyridine N,N'-dioxide), a new iodobismuthate hybrid with formula of(H_2 DPDO)2(Bi_4 I_(16))(1) was synthesized under solvothermal conditions. The Bi_4 I_(16)~(4-) tetramer is built from four edge-sharing BiI_6 octahedra. I···I interactions stabilize the structure and contribute to the structural extending from 0-D cluster to 1-D chain. The broader absorption band and lower energy gap of 1.76 eV are led by strong I···I interactions, so the small and rigid template can result in strong halogen···halogen interaction, which will be beneficial for its charge transfer. The photocurrent response property of this complex was discussed, and its mechanism has also been proposed.  相似文献   

2.
The coordination polymer[Zn_(1.5)(2,2?,4??-tpt)(tpa)_2]_n(2,2?,4??-tpt=3,4-bis(2-pyridyl)-5-(4-pyridyl)-1,2,4-triazole,H_2tpa=terephthalic acid)has been obtained by solution evaporation method and characterized by elemental analysis,IR,TG and single-crystal X-ray diffraction.The title compound crystallizes in the triclinic system,space group P1,with a=10.331(3),b=10.596(1),c=14.966(3)?,β=99.029(0)o,V=1448.86(6)?~3,Z=2,D_c=1.668g/cm~3,μ=1.320 mm~(-1),F(000)=740,R=0.0359 and w R=0.0841 with I2σ(I)).In this polymer,the asymmetric unit contains two crystallographically independent Zn(II)ions in different coordination environments.Zn(1)ion is five-coordinated,forming a distorted tetragonal pyramidal geometry,while the Zn(2)ion is six-coordinated to get a distorted octahedral geometry.Each Zn(II)ion is linked by 2,2?,4??-tpt and H_2tpa ligands,forming an infinite 2D structure.The existence of O(8)–H(8)···O(2)hydrogen bonding interactions leads the 2D chains to generate a 3D structure.In addition,1 shows strong photoluminescent emissions in the solid state at room temperature,so it can be used as potential optical materials.  相似文献   

3.
A new coordination compound Zn(2,4?-bpt)2(H_2O)(1) based on the versatile ligand 2,4?-Hbpt(2,4?-Hbpt = 3-(2-pyridyl)-5-(4-pyridyl)-1H-1,2,4-triazole) was prepared by hydrothermal reactions. The structure of complex 1 has been characterized by X-ray single-crystal diffraction, elemental analysis, X-ray powder diffraction, IR spectrum analysis and thermogravimetric analysis. Single-crystal X-ray diffraction analysis indicates that the complex belongs to monoclinic system, space group C2/c with a = 23.877(3), b = 0.7483(9), c = 1.2492(2) ?, b = 92.681(2)°, V = 2230.6(4) ?3, Z = 4, Dc = 1.572 g/cm~3, m = 1.143 mm~(-1), Mr = 527.85 and F(000) = 1080. The final R = 0.0581 and w R = 0.0898 with I 2s(I). 1 is a 0D motif which is connected by hydrogen bonds to form a corrugated 1D pattern. In addition, 1 shows strong photoluminescent emissions in the solid state at room temperature which can be used as potential optical materials. Theoretical calculations based on density functional theory(DFT) were employed in order to explicate the stability and chemical reactivity of 2,4?-Hbpt with different conformations. The results indicated that conformation I is more stable and prior to coordination in the reactions.  相似文献   

4.
The double-stranded DNA (dsDNA) probe contains two different protein binding sites. One is for DNA- binding proteins to be detected and the other is for a DNA restriction enzyme. The two sites were arranged together with no base interval. The working principle of the capturing dsDNA probe is described as follows: the capturing probe can be cut with the DNA restriction enzyme (such as EcoR I) to cause a sticky terminal, if the probe is not bound with a target protein, and the sticky terminal can be extended and labeled with Cy3-dUTP by DNA polymerase. When the probe is bound with a target protein, the probe is not capable to be cut by the restriction enzyme because of space obstruction. The amount of the target DNA binding proteins can be measured according to the variations of fluorescent signals of the corresponding probes.  相似文献   

5.
The reactions of Co(ClO4)2·6H2O and Co(NO3)2·6H2O with the di-Schiff base ligand N,N'-bis-(1-benzimidazo-2-yl-ethylidene)-ethane-1,2-diamine (LA) in ethanol have been investigated. The reactions of LA with excess amount of cobalt salts yield the six-coordinate complexes [CoL2](ClO4)2·H2O 1 and [CoL2](NO3)2·H2O 2 as isolatable products (L = N-(1-benzimidazo-2-yl-ethylidene)-ethane-1,2-diamine), where L is a tri-dentate mono-Schiff base ligand, resulting from the hydrolysis of the precursor di-Schiff base LA. Both complexes were characterized by X-ray crystallography. Crystal data for complex 1: monoclinic, space group P21/c, a = 11.9214(10), b = 23.5828(17), c = 14.0387(12) , β = 135.219(4)o, C22H30Cl2CoN8O9, Mr = 680.37, V = 2780.1(4) 3, Z = 4, Dc = 1.625 g/cm3, μ(MoKα) = 0.876 mm-1, F(000) = 1404, the final R = 0.0725 and wR = 0.1530 for 5726 observed reflections (I > 2σ(I)). Crystal data for complex 2: monoclinic, space group P21/c, a = 18.2162(16), b = 10.0610(6), c = 18.593(2) , β = 130.099(3)o, C22H30CoN10O7, Mr = 605.49, V = 2606.5(4) 3, Z = 4, Dc = 1.543 g/cm3, μ(MoKα) = 0.722 mm-1, F(000) = 1260, the final R = 0.0619 and wR = 0.1429 for 5194 observed reflections (I > 2σ(I)). X-ray diffraction analysis reveals that each cobalt atom in the two complexes is chelated by six nitrogen atoms from two tridentate ligands L, exhibiting a slightly distorted octahedral coordination sphere. In both complexes, the strong hydrogen-bonding interactions between the lattice waters and N-H groups of the ligands result in 1D chains which are further connected by ClO4-(or NO3-) groups to form a 3D framework. In complex 2, the strong π-π interactions increase the stability of the structure.  相似文献   

6.
A homochiral complex, Zn3(Hsalen)2(Py)4(H2O)2 (salen = (1R,2R)-(-)-diamino-cyclohexane-N,N'-biscarboxyl-salicylidene) 1, has been synthesized by solvothermal procedure and characterized by IR, microanalysis, TGA, powder and single-crystal X-ray crystallography. It crystallizes in monoclinic space group P2 with a = 10.9439(7), b = 10.1722(6), c = 27.3450(17), β = 97.5060(10)o, V = 3018.1(3) 3, Z = 2, Zn3(Hsalen)2(Py)4(H2O)2, Mr = 1363.33, Dc = 1.500 g/cm3, F(000) = 1408, μ = 1.257 mm-1, GOOF = 1.042, the final R = 0.0601 and wR = 0.1464 for 10322 observed reflections with I 2σ(I). The coordination polymer 1 possesses a 1D infinite zigzag chain architecture constructed by strong hydrogen bonding interactions and the polymeric chains are further assembled into a 2D supramolecular network structure via C-H···π interactions between the cyclohexane and aromatic rings of the ligand of adjacent chains. Simultaneously, π···π stacking interactions play an important role in forming the 2D supramolecular framework.  相似文献   

7.
We present a simple method to increase the efficiency of a direct ethanol fuel cell by a periodic modulation of the load(pulsed mode). The fuel cell was periodically short circuited with a resistor(1 Ω) for a few seconds(high load period) followed by a low load period of up to 100 s when the resistor was disconnected. The open circuit voltage(OCV) values before and after the short circuit of the cell showed an increase of up to 70 mV. The higher OCV was due to the oxidation and removal of strongly adsorbed CO during the electric short circuit when the electric potential of the anode was increased to be close to the cathode potential. The depoisoned anode surface was much more active directly after the short circuit. The slow decrease of the OCV observed after the short circuit was caused by the subsequent poisoning of the anode surface, which can be neutralized by another short circuit. In general, a stable increase in cell performance was obtained by repetition of the electric short circuit. The data showed that the pulse mode gave an increase in the power generated by the direct ethanol fuel cell by up to 51% and was 6% on average. It is anticipated that this mode of operation can be used also in different types of polymer electrolyte membrane fuel cells where CO poisoning is a problem, and after optimization of the parameters, a much higher gain in efficien-cy can be obtained.  相似文献   

8.
The kinetics of oxidation of glycol by dihydroxydiperiodato nickelate ( Ⅳ) complex (DDN) was studied by spectrophotometry in aqueous alkaline medium in a temperature range of 25-40℃. The reaction was found to be first order with respect to Ni( Ⅳ ) and also to be first order with respect to glycol. The rate increases with the increase in [OH ] and decreases with the increase in [IO-4], showing that dihydroxymonoperiodatonickelate ( Ⅳ )(DMN) is the reactive species of oxidant. Salt effect indicated that the reaction is of ion-dipole type. No free radical was detected. A mechanism of an inner-sphere two-electron transfer reaction involving a preequilibrium between DDN and DMN is proposed, and the rate equation derived from the mechanism can explain all experimental observations. Activation parameters of the rate-determing step and the equilibrium constants were calculated.  相似文献   

9.
A new coordination polymer {[Cd(C_(21)H_(14)N_6)(C_8H_4O_4)]·H_2O}_n(1) was synthesized by an elaborate design via the reaction of 3-(2,6-di(pyrazin-2-yl)pyridin-4-yl)-1H-indole(bppi),1,4-benzene-dicarboxylic acid(H2bdc) and cadmium(Ⅱ) nitrate in CH_3OH/H_2O mixed solvents. Complex 1 crystallizes in orthorhombic,space group Ccca with a = 20.012(4),b = 31.881(6),c = 19.808(4) ?,V = 12638(4) ?~3,Z = 16,C_(29)H_(20)CdN_6O_5,M_r = 644.91,D_c = 1.356 g·cm~(-3),μ = 0.735 mm~(-1),F(000) = 5184,GOOF = 1.046,the final R = 0.0405 and wR = 0.1063 for 6870 observed reflections(I 2σ(I)). The Cd(Ⅱ) centre is hepta-coordinated by three N and four O atoms from one bppi terminal ligand and two bdc2– ligands,respectively,displaying a capped trigonal prism geometry. Structure extension gives coordination polymeric chains,in which the bdc2– linkers connect Cd(Ⅱ) cations into a one-dimensional(1D) coordination polymer along the c axis,giving zigzag chains with the Cd···Cd separation of 11.178(1) ?. The adjacent bppi terminal ligands in the chains are anti-periplanar conformation. The three-dimensional(3D) structure is stabilized by π···π stacking and hydrogen-bonding interactions to form a supramolecular self-penetrating network with 1D channels. In 1,there are voids 2999.7 ?~3 with 23.7% of per unit cell volume. Thermal analysis indicates that the framework of 1 is stable until 651 K and the photoluminescence of 1 in the solid shows very weak fluorescence at 382 and 560 nm upon excitation at 310 nm.  相似文献   

10.
Poly(methyltetraphenylphenylsilylene-co-bis(methylphenylsilyl)acetylene) (PSA) was synthesized by the cocondensation reaction of methyltetraphenylphenyldichlorosilane and bis(chloromethylphenylsilyl)acetylene with sodium in toluene. The PSA thus obtained was soluble in most organic solvents, and its molecular weight was smaller than that of poly[(disilanylene)acetylenes] with alkyl- or aryl-substitution because of the great steric congestion of tetraphenylphenyl groups. The optical and electronic properties of the polymer were investigated. The results show that PSA has strong UV absorption and fluorescence emission, the maximum UV absorption wavelength of PSA is 330 nm, which shows a considerable red-shift in comparison with that of poly(methylphenylsilylene-co-methylphenylsilylacetylene) (PSI) and alkylsubstituted poly[(disilanylene)acetylenes]. A strong photoluminescence band at 470 nm in THF and 432 nm in benzene can be observed in the visible region, respectively. Treatment of the films of PSA with I2 vapor afforded conducting films. The conductivity of PSA thin film doped with I2 was measured to be 0.35 Scm-1 in the air which is lower than that of poly(methyltetraphenylphenylsilylene-co-bis(methylphenylsilyl)phenylene), but higher than that of σ-π polymers without tetraphenylphenyl groups. As an explanation, the tetraphenylphenyl group is a large π-electron-conjugated group; after being introduced to the Si atoms of the polysilanes, the interaction between π-electrons of the tetraphenylphenyl groups and the σ-electrons conjugated along the Si-Si bonds is increased strongly, and the σ-electrons can be conjugated more extensively along the main chain of the polysilanes.  相似文献   

11.
A new complex [Cd_2(L)_2(Cl)_2(H_2O)]_n(1) was synthesized by reacting CdCl_2·2.5 H_2O with 4-(1,2,4-triazol-4-yl)phenylacetic acid(HL) ligand.The structure of the complex was characterized by single-crystal X-ray diffraction,IR spectroscopy,elemental analysis and PXRD.Complex 1 crystallizes in triclinic,space group P21/c with a = 11.4303(8),b = 14.1792(10),c = 14.6857(10) ?,β = 96.3780(10)o,V = 2365.4(3) ?~3,Z = 4,C_(20)H_(16)Cl_2N_6O_5Cd_2,M_r = 716.09,D_c = 2.011 g/cm3,μ = 2.069 mm~(-1),S = 1.051,F(000) = 1392,the final R = 0.0458 and wR = 0.0949 for 5402 observed reflections(I 2σ(I)).Complex 1 is a two-dimensional(2D) layer structure and non-covalent bonding interactions such as C–H···π and π···π extend the 2D to form a three-dimensional supramolecular polymer.  相似文献   

12.
The reaction of the reduced Schiff base HL(N-(4-hydroxybenzyl)-L-serine) with Zn(CH_3COO)_2·2H_2O in aqueous solution afforded [Zn(L)_2]·3H_2O(I). The complex has been characterized by elemental analysis, FT-IR, powder X-ray diffraction, electrospray ionization mass spectrometry and single-crystal X-ray diffraction. Complex I crystallizes in the orthorhombic system, space group P212121, with a=9.197(2), b=10.445(2), c=24.149(5) ?, V=2319.8(8) ?~3, Z=4, C_(20)H_(30)N_2O11 Zn, M_r=539.83, Dc=1.546 g·cm~3, μ=1.122 mm~(-1), F(000)=1128, GOOF=0.971, the final R=0.0206 and w R=0.0506 for 4346 observed reflections(I 2σ(I)). In complex I, each Zn(II) ion coordinates with three carboxyl oxygen atoms and two amine nitrogen atoms from three L-anions, forming a distorted five-coordinated trigonal bipyramidal geometry. Complex I exhibits a 1D wavy chain structure that is extended by hydrogen-bonding interactions to form a supramolecular network. The bioactivity of the complex as a potential PTPs inhibitor in vitro was investigated, displaying potent inhibition against PTP1B(IC_(50), 0.24 μM) and TCPTP(IC_(50), 0.53 μM) with a moderate selectivity.  相似文献   

13.
This article describes the preparation and liquid crystalline properties of a new homologous series of 4-(4-bromopropyloxy)-4’- (4-alkyloxybenzylidene)anilines in which the phenyl ring is armed by a bromopropyloxy chain.The thermal behavior and mesomorphic properties of the synthesized compounds were studied with particular attention given to the correlation between their phase transition temperatures and anisotropic change influenced by molecular structure.All the members displayed enantiotropic smectic phase except for the homologue with the longest alkyloxy chain(R = C18H37),exhibiting only monotropic characteristic. The presence of bromine atom from the propyloxy side chain is found to be capable of altering and influencing the mesomorphic properties.  相似文献   

14.
Luminescence of europium (Ⅲ),europium(Ⅱ) and terbium(Ⅲ) has been observed in Bas(PO4)2:Eu,Tb phosphors which are synthesized in air atmosphere.The valence state of europium is influenced by amount of terbium.It is notable that the relative intensity of the emission spectra peaks corresponding to Eu2+ is increased if the amount of Tb3+ is increased.These phenomena can be explained by an electron transfer mechanism.We predict a new kind of two-rare-earth codoped trichromatic phosphors in Ba3(PO4)2 matrix.  相似文献   

15.
Zn(Ⅱ), Ni(Ⅱ) and Co(Ⅱ) compounds(1~3) based on 2-(2-pyridyl)benzothiazole(bpt) and terephthalic acid(PTA) were synthesized. The crystal structures of [Zn(bpt)(PTA)2](1), [Ni(bpt)(PTA)2](2), and [Co(bpt)(PTA)2](3) have been determined by single-crystal X-ray diffraction analysis, which shows that all the three complexes belong to monoclinic system with space group P21/c. Time-dependent density functional theory(TD-DFT) calculation is performed on a reference structure of compound 3. The excited electrons mainly localized at the π* of ligand 2-(2-pyridyl)benzothiazole, which will be convenient for them to bind with the DNA reacting sites. Fluorescence spectroscopy, ultraviolet(UV) spectroscopy and viscosity were used to characterize the interaction of the compounds with Calf thymus DNA(CT-DNA). The results indicate that compounds 1~3 bind to CT-DNA and have a strong interaction with DNA. The compounds can probably bind to CT-DNA via a non-intercalative mode as concluded by studying the viscosity of a DNA solution in the presence of the compounds. This combination can effectively break DNA, which speculates that these three compounds may interact with the cancer cell DNA in this binding mode, thereby damaging the cancer cells.  相似文献   

16.
《结构化学》2021,40(6)
Two triphenylmethylphosphonium/haloplumbate hybrids,i.e.,[(PPh_3Me)_2(Pb_2I_6)·CH_3CN]_n(1) and[(PPh_3Me)(PbBr_3)]_n(2),have been prepared,in which the(PbX_3)_n~(n-) nanochains built from face-sharing PbX_6 octahedra are surrounded by organic templates to assemble the core-shell quantum well.Besides,C-H…πinteractions among Ph_3 PMe~+ cations can also be detected,which give rise to the 2-D organic layer of 1 and 1-D chain for 2.The good water stabilities could be induced by the strong C-H…π interactions,which can deter the hydrolysis reaction.The energy band gaps of this work mainly derive from the charge transfer of organic components,but their luminescence stems from the inorganic(PbX_3)_n~(n-) nanochains with co-existence of free excitons and self-trapped excitons.At temperature lower than 117 K,strong quantum confinement will rule out the free excitons,and self-trapped excitons will dominate,resulting in red-shift luminescence.Moreover,effective and repeatable photocurrent responses can be found in these hybrids.  相似文献   

17.
<正>The crystal of Nd0.06Y0.94Sr6Sc(BO3)6 with the dimensions up to 35 mm × 28 mm × 13 mm was grown by a top-seeded solution growth method from Li6B4O9 flux. The grown crystal was characterized by X-ray powder diffraction. The optical absorption of the crystal shows that it has a strong absorption band at 8070 A, and the absorption coefficient is 2.17cm-1 with a FWHM of 41 A, which can match with the wavelength of the diode-laser (LD) and is suitable for the LD pumping. Based on the Judd-Ofelt theory, the three parameters of line oscillator strength Ω(λ) (λ = 2, 4 and 6) of the Nd3+ion in the crystal were calculated as follows: Ω2= 1.194 × 10-20, Ω4= 4.186 × 10-20 and Ω6 = 3.351 × 10-20cm2, which are relatively larger. The results indicate that the crystal Nd0.06Y0.94Sr6Sc(BO3)6 may be a kind of high-efficient laser material for diode-pumped.  相似文献   

18.
肖光参 《结构化学》2014,33(11):1689-1696
A new inorganic-organic hybrid constructed from biisoquinoline dication and tin halide, [(BIQBT)(Sn Cl6)]n(1, BIQBT = 1,4-bis(isoquinoline) butane), has been synthesized and structurally determined by X-ray diffraction method. 1 crystallizes in the monoclinic system, space group Cc with Mr = 644.82, a = 16.589(3), b = 18.388(4), c = 8.5532(17), β = 108.75(3)°, V = 2470.6(9) 3, Z = 4, Dc = 1.736 g/cm3, F(000) = 1281, μ(Mo Kα) = 1.697 mm–1, the final R = 0.0197 and w R = 0.0493 for 4614 observed reflections with I 2(I). 1 consists of BIQBT2+dications and mononuclear hexachloridostannate Sn Cl62- anion, and hydrogen bonds among them contribute to the formation of a 1-D chain. Strong fluorescence can be detected in 1, which was explained by theoretical calculation. Its electrochemical behavior was investigated, and the theoretical calculations reveal that the π···π stacking interaction is dominated for their structural stabilization.  相似文献   

19.
The reaction of CdCl2 with 6,7-dicyanodipyridoquinoxaline (DICNQ) by solvothermal reaction gives rise to a coordination polymer [CdCl2(DICNQ)]n 1. Single-crystal X-ray diffraction analysis reveals that the compound in space group Pbcn creates 1-D chloro-bridging chains. Crystal data for 1: a = 6.756(1), b = 35.371(6), c = 7.027(1) , V = 1679.1(5) 3, Z = 4.00, C16H6CdCl2N6, Mr = 465.57, Dc = 1.842 g/cm3, μ = 1.630 mm-1, F(000) = 904, S = 1.005 and T = 293(2) K. The final R = 0.0376 and wR = 0.1029 for 1291 observed reflections with I > 2σ(I), and R = 0.0499 and wR = 0.1125 for all data. The 1-D chloro-bridging chains are parallel-stacked in the a and b directions, and further stabilized through π-stacking interactions, hydrogen-bonding interactions and C≡N···π interactions to generate a 3-D structure. Compound 1 displays intense bluish-green photoluminescence from the intraligand charge-transfer of the DICNQ ligand and the Cl--to-DICNQ charge-transfer mechanism which is probed by the density of states (DOS) calculations.  相似文献   

20.
Researches on multifunctional molecular materials with both nonlinear optical activity and fluorescence properties have received much interest in molecular chemistry since they have wide application prospects. Here a novel ionic compound 2(BPP)~+·[Mn(NCS)_4]~(2-)(1) was synthesized via the assembly of benzyltriphenylphosphorus chloride, isothiocyanate and manganese chloride, which displays both strong SHG response and purple luminescence. Compound 1 belongs to monoclinic system and crystallizes in Cc space group. X-ray single-crystal diffraction analysis shows that Mn~(2+) ions are tetra-coordinated with N atoms of four NCS-ions through forming a distorted tetrahedral configuration. The anion Mn(NCS)_4~(2-) forms a 1D chain structure through strong S···S interaction. At the same time, there are abundant C–H···S and π···π interactions, which further accumulate into a three-dimensional supramolecular structure. Solid-state fluorescence studies show that the complex 1 has strong purple fluorescence with emission wavelength of 396 nm under excitation wavelength 248 nm. In particular, the second harmonic generation(SHG) measurements show that compound 1 has nonlinear optical activity and its SHG response is 2.25 times that of standard potassium dihydrogen phosphate(KDP). This multifunctional molecular material with SHG response and purple fluorescence is of great significance for the development of new metal organic complexes with potential application prospects.  相似文献   

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