Off-on-off luminescent switching of a dye containing imidazo[4,5-f][1,10]phenanthroline

A new acid-base fluorescent switch containing both imidazo[4,5-f][1,10]-phenanthroline and triphenylamine groups has been synthesized.Its fluorescence emissions and absorptions can be reversibiy changed through protonation/deprotonation of imidazole and amine moiety by controlling the intramolecular charge transfer(ICT) process,leading to off-on-off fluorescent molecular switching.     

Green synthesis of naphtho[2,3-f]quinolin-13-one and naphtho[2,3-a]acridin-1(2H)-one derivatives catalyzed by heteropoly acid supported montmorillonite K-10 clay

Herein, synthesis of a series of naphtho[2,3-f]quinolin-13-one and naphtho[2,3-a]acridin-1(2H)-one derivatives directly by one-pot multi-component reaction of 1,3-dicarbonyl compounds (1,3-indanedione/1,3-cyclohexanedione), 2-aminoantharacene/2-naphthylamine and various substituted aldehydes under solvent-free conditions using heteropoly-11-molybdo-1-vanadophosphoric acid supported on montmorillonite K-10 clay catalyst (10% PVMoK-10) is reported. The successful formation of naphtho[2,3-f]quinolin-13-one and naphtho[2,3-a]acridin-1(2H)-one derivatives was confirmed by various spectroscopic techniques. This study offers a green approach for the synthesis of novel quinolinone derivatives.     

以对苯二甲酸及咪唑并[4,5-f][1,10]邻菲咯啉为配体的镉(Ⅱ)、锌(Ⅱ)配合物的构筑及晶体结构

在水热条件下,以对苯二甲酸(H2bdc)和咪唑并[4,5-f][1,10]邻菲咯啉(Imphen)为配体构筑了两种配合物[Cd(bdc)(Imphen)(H2O)]n·nH2O(1)和[Zn(bdc)(Imphen)(H2O)]n·nH2O(2),并利用元素分析和X-射线单晶衍射对其结构进行了表征。结构分析表明:bdc2-在2个配合物中展示了不同的配位模式,配合物1和2都具有一维链状结构,并且都通过分子间氢键和π-π相互作用形成三维网状结构。此外,对配合物的热稳定性和发光性质也进行了研究。     

Synthesis, Structure and Photoluminescence of a New Cd(Ⅱ)Coordination Polymer Based on 4-(Carboxymethoxy)-benzoic Acid and 1,10-Phenanthroline Derivative

A new 1D coordination polymer, [Cd2(L1)2(L2)2]·H2O (1, H2L1 = 4-(carboxy-methoxy)benzoic acid and L2 = 2-(4-fluorophenyl)-1H-imidazo[4,5-f][1,10]phenanthroline), has been hydrothermally synthesized and characterized by elemental analysis and single-crystal X-ray diffraction. It crystallizes in triclinic, space group Pī with a = 9.985(5), b = 10.768(5), c = 12.512(5), α = 68.959(5), β = 80.354(5), γ = 79.663(5)°, V = 1227.4(10) 3, Z = 1, C56H36Cd2F2N8O11, Mr = 1259.73, Dc = 1.704 g/cm3, F(000) = 630, μ(MoKa) = 0.949 mm-1, R = 0.0261 and wR = 0.0655. The L1 anions link the neighboring Cd(II) atoms to form a 1D double chain structure. The L2 ligands are alternately located on both sides of the double chains. More interestingly, the lateral L2 ligands from adjacent double chains are paired to furnish strong π-π interactions, yielding a 2D supramolecular layer. N-H···O, O-H···N and O-H···O hydrogen bonds further stabilize the structure of 1. The luminescent property of 1 was studied in solid state at room temperature.     

Temperature Influence on Divergence Angles of Quartz Crystal Wollaston Prism

We propose a structural angle and main refractive indices as two key factors to understand the temperature influence on the divergence angles of the Wollaston prism. The temperature influence on the divergence angles of quartz crystal Wollaston prism is studied theoretically. The results show that divergence angles decrease with increasing temperature, while the divergence angle of e-light decrease more quickly than that of o-light. The testing system is established to verify the above results, and the experimental results are in agreement well with the theoretical analysis.     

Effect of Electrical Field on Colloidal CdSe/ZnS Quantum Dots

We fabricate the hybrid films of colloidal CdSe/ZnS quantum dots (QDs) and poly(9-vinylcarbazole) (PVK) sandwiched between two electrodes. The voltage and temperature dependences of the electroluminescence (EL) are measured. The quantum-confined Stark effect of colloidal QDs is clearly observed. To explore the mechanism in the QD EL, hybrid films are fabricated with different concentrations of colloidal QDs. Electrons and holes are proposed to be separately transported in QDs and PVK, respectively.     

Spin-flip shot noise in a quantum dot coupled to carbon nanotube terminals responded by a rotating magnetic field

We have investigated the spectral density of shot noise of the system with a quantum dot (QD) coupled to two single-wall carbon nanotube terminals, where a rotating magnetic field is applied to the QD. The carbon nanotube (CN) terminals act as quantum wires which open quantum channels for electrons to transport through. The shot noise and differential shot noise exhibit novel behaviors originated from the quantum nature of CNs. The shot noise is sensitively dependent on the rotating magnetic field, and the differential shot noise exhibits asymmetric behavior versus source-drain bias and gate voltage. The Fano factor of the system exhibits the deviation of shot noise from the Schottky formula. The super-Poissonian and sub-Poissonian shot noise can be achieved in different regime of source-drain bias.     

On atomic analogue of Landau quantization

We have studied the physics of atoms with permanent electric dipole moment and nonvanishing magnetic moment interacting with an electric field and inhomogeneous magnetic field. This system can be demonstrated as the atomic analogue of Landau quantization of charged particles in a uniform magnetic field. This Landau-like atomic problem is also studied with space-space noncommutative coordinates.     

Quantum non-demolition measurement of photon number using weak nonlinearities

We propose an alternative method for the quantum non-demolition measurement of photon numbers wherein weak cross-Kerr nonlinearities are to be used. The usual approach to quantum non-demolition measurements of quantum number involves encoding the photon number, through a cross-Kerr interaction, into a phase shift of a probe coherent state which is then detected through balanced homodyning. Weak nonlinearities produce small phase shifts which are difficult to detect and distinguish. In the method we propose, unbalanced homodyning acts as a displacement operator on the probe beam coherent state such that the cross-Kerr interaction encodes the photon number into the amplitude of a new coherent state. The value of the photon number can be determined by inefficient photon counting on the new coherent state. Our proposed method requires fewer resources than does the usual approach.