2,5-di(thiophen-2-yl)thiazolo[5,4-d]thiazole-based donor-acceptor type copolymers for photovoltaic cells

Alternating donor-acceptor type copolymers, poly[{5,11-di(9′-heptadecanyl)indolo[3,2-b]carbazole}-alt-{2,5-di(thiophen-2-yl)thiazolo[5,4-d]thiazole-5,5′-diyl}] (PIC-TZ) and poly[{6,6′,12,12′-tetraoctylindeno[1,2-b]fluorene}-alt-{2,5-di(thiophen-2-yl)thiazolo[5,4-d]thiazole-5,5′-diyl}] (PIF-TZ), were synthesized and examined for applications in polymeric photovoltaic cells. The polymers have a fused coplanar main backbone with good planarity for intermolecular packing and high charge mobility. The indolocarbazole and indenofluorene units contain two or four binding sites for alkyl substituents that have pronounced solution processiblity compared to the carbazole and fluorene moieties. The number-average molecular weights (M_n) of the synthesized polymers were determined to be 11,000 g/mol (PDI = 2.27) for PIC-TZ, and 17,000 g/mol (PDI = 1.77) for PIF-TZ. The optical band gap of PIC-TZ and PIF-TZ in film was determined to be 2.14 eV and 2.21 eV, respectively, and an electrochemical study confirmed the desirable HOMO/LUMO levels of the copolymers, which enabled efficient electron transfer and a high open circuit voltage (V_OC) when blending them with fullerene derivatives. The space charge limited current mobility measurements showed a hole mobility of 10⁻³ cm² V⁻¹ s⁻¹ for the copolymers. When the polymers were blended with [6,6]phenyl-C₆₁-butyric acid methyl ester (PCBM), PIC-TZ showed the best performance with V_OC, short-circuit current and power conversion efficiency of 0.86 V, 4.16 mA/cm² and 1.64%, respectively, under AM 1.5G illumination conditions (100 mW cm⁻²).     

(E,E)-1,4-双{2''-[5''-(B,B-二甲基苯硼)-2-噻吩基]乙烯基}-苯分子双光子吸收特性的理论研究

在密度泛函水平上,利用响应函数方法,研究了分子的单光子和双光子吸收特性.计算出了该分子在低能量范围内的最大双光子吸收截面为6.47×10-47cm4s/photon,与实验符合的较好.研究结果表明该分子具有较强的双光子吸收特性,是较好的双光子吸收材料.     

3-羟基-2-萘甲酸-铬(Ⅲ)配合物与牛血清白蛋白作用的光谱研究

研究了3-羟基-2-萘甲酸铬(I)配合物[Cr(3-HNA)(en)2]Cl的紫外-可见吸收光谱和荧光光谱性质.在pH 7.4.0.05mol.L-1 Tris-HCl缓冲条件下通过荧光光谱技术,研究了BSA与[Cr(3-HNA)(en)2] 间的相互作用,测定了反应的结合常数与结合位点数.     

A density functional theory (DFT) study of the doping effect on 2-cyano-3- [4 (diphenylamino) phenyl] acrylic acid

In this work, the DFT method (B3LYP) with the base 6-31+G** was used to study the influence of doping on the molecule 2-cyano-3- [4- (diphenylamino) phenyl] acrylic. To do this, the dipole moment (μ), the polarizability (α0), the anisotropy of the polarizability (Δα), the hyperpolarizability (β0), the gap HOMO-LOMO (HL gap), the dielectric constant (ε), the electric susceptibility (χ), the refractive index (η) and the thermodynamic properties of the different molecules have been calculated. The polarizability, the first hyperpolarizability and the HL gap enable us to conclude that the doping with titanium dioxide leads to new interesting molecules for applications in the design of new nonlinear and optoelectronic materials.     

Spectral behavior study of 3-(4-dimethylamino-phenyl)-1-{6-[3-(4-dimethylamino-phenyl)-acryloyl]-pyridin-2-yl}-propanone

The photophysical properties such as singlet absorption, molar absorptivity, fluorescence spectra, fluorescence quantum yield (?_f) and transition dipole moment (μ₁₂) of 3-(4-dimethylamino-phenyl)-1-{6-[3-(4-dimethylamino-phenyl)-acryloyl]-pyridin-2-yl}-propanone (DMAPAPP) have been studied in different media. DMAPAPP exhibits a large red-shift in both absorption and emission spectra as the solvent polarity increases, indicating a large change in dipole moment of molecule upon excitation. The fluorescence quantum yield depends on the nature of the solvent. The absorption and emission spectra of DMAPAPP in dioxane–water mixture are also studied. The effect of different type of surfactants to determine their critical micellar concentration (CMC) and the microemulsion effect on the electronic absorption and emission spectra of DMAPAPP are recorded. The effect of acidity on the electronic absorption and emission spectra of DMAPAPP is studied to determine the pK_a and pK_a^? values.     

A Double Isotopic Labelling Study of the Infrared Spectra of the Linkage Isomers [Pd(bipy)(SCN)2], [Pd(bipy)(NCS)2] and Related Complexes

Abstract

The IR spectra of the linkage isomers [Pd(bipy)(SCN)₂] and [Pd(bipy)(NCS)₂] have been determined in the C≡N stretching region (2200–2000 cm^?1) and below 500 cm^?1. The band shifts resulting from deuteration of the 2,2′-bipyridine (bipy) ring and ¹⁵NCS-labelling are shown to provide a ready means for distinguishing between the internal ligand modes, the μPd-N(bipy) and μPd-SCN/μPd-NCS vibrations. The assignment technique has been further extended to the complexes [Pt(bipy)(SCN)₂] and [Pd(phen)(SCN)₂] (phen = 1,10-phenanthroline). Finally, a comparison between the IR spectra of [Pd(bipy)(NCO)₂], [Pd(bipy)(NCS)₂] and [Pd(bipy)(SCN)₂] reveals that the frequencies μM-NCO, μM-NCS and μM-SCN decrease in the sequence NCO > NCS > SCN.     

Angle-resolved photoemission study of the MX-chain compound [Ni(chxn)(2)Br]Br(2): spin-charge separation in hybridized d-p chains

We report on the results of angle-resolved photoemission experiments on a quasi-one-dimensional (1D) MX-chain compound [Ni(chxn)2Br]Br2, which shows a gigantic nonlinear optical effect. A "band" having about 500 meV energy dispersion is found in the first half of the Brillouin zone, but disappears at kb/pi approximately 1/2. These spectral features are well reproduced by the d-p chain model with a small charge-transfer energy Delta compared with that of 1D Cu-O compounds. We propose that this smaller Delta is the origin of the absence of clear spin-charge separation in the photoemission spectra and the strong nonlinear optical effect.     

Substituent effect study on 13Cβ SCS of styrene series. A Yukawa–Tsuno model and Reynolds dual substituent parameter model investigation

The Yukawa–Tsuno (Y–T) and Reynolds dual substituent parameter (DSP) models have been used to model ¹³C substituent chemical shift (SCS) of the C_β atom of 19 series of para‐substituted styrenes (X‐C₆H₄CR?CYW) with variable electronic and structural demands in the side‐chain. The best fit of the Y–T model was better than that of the Reynolds DSP model for most of the studied series. A high correlation was found between the ρ value of the Y–T model and ρ_F value of the Reynolds DSP model. The ρ value, which reflects the sensitivity of ¹³C_β SCS to the substituent field effect, was found to be influenced by the group W on the C_β atom. A W group that enhances the para‐substituent π‐polarization of the side‐chain has a higher ρ value than its counterpart W groups that induce counter π‐polarization in the side‐chain. The series with W in an E‐configuration to the aryl ring has higher ρ value than corresponding Z series. A lower ρ value is observed when W induces a counter π‐polarization of the side‐chain (as with NO₂ and COMe) or when the R substituent imposes a 65° dihedral angle between the side‐chain and the para‐substituted benzene ring (as with t‐Bu). When the W group is a heterocyclic ring, the closer the heteroatom is to C_β, the lower the ρ value is due to the greater counter π‐polarization. The two components of the substituent effect on ¹³C _β SCS, namely the field effect and resonance effect, behave inversely. The resonance demand (r⁺ value) increases, as the Y and/or W groups become more electron‐withdrawing (EW). The series with W as a hetrocyclic ring develop negative charge at the carbon atom of the hetrocyclic ring adjacent to C_β (and to which the styryl moiety is attached) and has a lower r⁺ value than those which fail to do so. The lowest r⁺ value was for those series with a 65° dihedral angle. Copyright © 2007 John Wiley & Sons, Ltd.     

金(I)催化丙二烯基化合物构建螺环[4,5]癸烷骨架的计算研究

采用B3LYP-D3(BJ)计算方法研究了金催化丙二烯基化合物合成螺环[4,5]癸烷骨架的反应机理。通过SMD模型在实验对应的CH3CN溶剂体系中进行单点能量计算得出更准确的能量。计算研究表明,该反应包括三个主要的步骤：烯丙基和乙烯基端基碳原子的分子内环加成、四元环重构为五元环的半频哪醇重排过程、消除反应释放催化剂并得到产物。结果显示第一步是反应的决速步骤,其活化自由能相对较低为70.18 kJ/mol,表明金催化的合成反应在室温条件下能够发生。     

Efficient synthesis of new functionalized 2-(alkylamino)-3-nitro-4-(aryl)-4H-benzo[g]chromene-5,10-dione

Molecular Diversity - Structurally diverse benzo[g]chromenes were conveniently synthesized by one-pot, multi-component reaction of N-alkyl-1-(methylthio)-2-nitroethenamine (derived from the...     

(4-溴甲基双环[4.4.1]-1,3,5,7,9-十一碳五烯基-3-)甲醇环氧化反应机理的理论研究

采用量子化学的密度泛函理论(DFT),在B3LYP/6 31G*水平上研究了(4 溴甲基双环[4. 4. 1] 1, 3, 5,7, 9 十一碳五烯基3 )甲醇环氧化反应机理,在对反应物和产物几何结构优化的基础上,搜索优化了反应的过渡态结构,通过振动分析和内禀反应坐标(IRC)跟踪方法对过渡态及其所处的反应路径进行了确认,并用电荷密度拓扑分析方法考察了反应过程中旧键断裂和新键形成的细节.计算结果表明,该反应中的消除反应和成环反应是协同进行的,溴化氢消除反应中的氢来自与O( 22 )相连的羟基氢,反应的活化势垒为139. 2kJ/mol,反应放热25. 1kJ/mol.     

三桥连双铁(III)配合物[Fe_2(IDB)_2(O)(CH_3CO_2)_2]Cl_2·CH_3OH的晶体结构及其傅立叶变换拉曼光谱(英文)

合成了一种新的三桥连双铁 (III)配合物 [Fe2 (IDB) 2 (O) (CH3CO2 ) 2 ]Cl2 ·CH3OH ,IDB为N ,N’ -di(2’ -benzimidazolylmethyl)imine,利用单晶X射线衍射及其它谱学方法对所合成配合物进行了表征。每个双核单元的两个铁原子均通过一个氧原子和两个醋酸根连接 ,每个铁原子同时还与位于桥氧原子对位的三齿配体IDB重脂肪链上氮原子相结合 ,每个铁 (III)中心为一变形八面体结构。对该新化合物的拉曼光谱进行了研究并对一些谱峰进行了归属     

A computational study of nonparabolic conduction band effect on quantum wire transport (e.g. GaN)

We studied the physics insight the GaN (example) quantum wire FET transistors. The model is based on the four $\mathbf{k}{\cdot } \mathbf{p}$ k · p Kane band model. We have introduced closed compact model for the Einstein relation of the diffusivity to mobility ratio (DMR) in quantum wires. The model can be applied for both wide and narrow band gaps of nonparabolic conduction band dispersion. The model is related to the optical matrix elements between conduction and valence bands. We have used 1D electrostatic to model the electron density over the maximum energy point. We have studied the effects of gate-to-source and drain-to-source voltages on the DMR by calculating the electron density using flux theory. We observed that above the threshold the non-parabolic dispersion increases the DMR. Additionally, we have studied the nonparabolic effects on the Fermi level and found that for low doping concentrations, the nonparabolic effect must be considered and an accurate calculation for the optical matrix elements is needed.     

1H and 13C NMR Determination of the Enantiomeric Purity of Substituted 4-Amino-3- (thien-2-Yl)-Butyric Acids and 4-Amino-3-(Benzo[b]Furan-2-yl)-Butyric Acids,Ligands of the GabaB Receptor.

The enantiomeric composition and absolute configuration of 4-Amino-3-(benzo[b]furan-2-yl)-Butanoic Acids and of 4-Amino-3-(thien-2-yl)-Butanoic Acids 1 may be accurately determined by ¹H and ¹³C nuclear magnetic resonance analysis of the corresponding derivatives 3 prepared by reaction with chiral reagents. Correlation with HPLC is signaled.     

Deep-Red Phosphorescent Iridium(III) Complexes Containing 1-(Benzo[b] Thiophen-2-yl) Isoquinoline Ligand: Synthesis,Photophysical and Electrochemical Properties and DFT Calculations

Four new bis-cyclometalated iridium(III) complexes, [Ir(btq) ₂phen] [PF₆] (3a), [Ir(btq) ₂bpy] [PF₆] (3b), [Ir(btq) ₂dtbipy] [PF₆] (3c) and [Ir(btq) ₂pic] (3d) (btq?=?1-(benzo[b] thiophen-2-yl) isoquinoline, phen?=?1,10-phenanthroline, bpy?=?2,2′-bipyridine, dtbipy?=?4,4′-di-tert-butyl-2,2′-bipyridine, pic?=?picolinic acid) have been synthesized and fully characterized. The crystal structure of 3a has been determined by X-ray analysis. The photophysical and electrochemical properties of these new complexes 3a???3d have been studied. The photoluminescence spectra of all Ir(III) complexes exhibit deep-red emission maxima at 682, 682, 683 and 698 nm, respectively. The most representative molecular orbital energy-level diagrams and the lowest energy electronic transitions of 3a???3d have been calculated with density functional theory (DFT) and time-dependent DFT (TD???DFT). The results show that the pic ancillary ligand of complex 3d influences the absorption and emission energies with a further red-shift relative to other three complexes 3a???3c.     

Discovery of ( ±)-3-(1 H -pyrazol-1-yl)-6,7-dihydro-5 H -[1,2,4]triazolo[3,4- b ][1,3,4] thiadiazine derivatives with promising in vitro anticoronavirus and antitumoral activity

A new series of (?±)-(3-(3,5-dimethyl-1H-pyrazol-1-yl)-6-phenyl-6,7-dihydro-5H-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazin-7-yl)(phenyl)methanones were efficiently synthesized starting from 4-amino-5-hydrazinyl-4H-1,2,4-triazole-3-thiol 1, acetyl acetone 2, various aromatic and heterocyclic aldehydes 3 and phenacyl bromides 4. All the newly synthesized compounds were tested for their antiviral and antitumoral activity. It was shown that subtle structural variations on the phenyl moiety allowed to tune biological properties toward antiviral or antitumoral activity. Mode-of-action studies revealed that the antitumoral activity was due to inhibition of tubulin polymerization.

Graphic abstract

     

在N2中[VnCr3—n（μ3—O）（μ—O2CCH3）6（THF）3]X[n=0—3,X=Cl^—1,ClO4^—,（VO5）0.5^—]及[VnFe3—n（μ3—O）（μ—O2CCH3）6（THF）3]X（n=0—3,X=Cl^—1）

The reaction behavior of the title complexes have been investigated by means of in situ IR in nitrogen atmosphere. It has been found that they enabled the acetic acid to convert to acetone and methane in different temperatures. The results indicate that the sequence of the ketonization reaction activity for the clusters was [V3OAT] > [VFe2OAT], [V2CrOAT] > [Fe3OAT], [VCr2OAT] > [Cr3OAT] [OAT = (mu 3-O) (mu-O2CCH3)6 (THF)3], and the sequence of the methanation reaction activity for the clusters was [Cr3OAT] > [VCr2OAT], [V2CrOAT] > [V3OAT] > [VFe2OAT], [Fe2OAH]. The ketonization reaction activity of [Fe3OAT] were obviously lower than that of [Fe3OAH] [OAH = (mu 3-O) (mu-O2CCH3)6 (H2O)3] and the methanation reaction activity of [Cr3OAT] were also much lower than that of [Cr3OAH]. The difference between [Fe3OAH], [Cr3OAT] and [Fe3OAH], [Cr3OAH] mentioned above were discussed.