[N-ethyl-4,4'-bipyridinium][ZnX_4](X = Cl or Br) with N-ethyl-4,4'-bipyridinium Generated In Situ:Syntheses, Structures, Fluorescence and TDDFT Calculations

Two new zinc bipyridinium compounds, [N-ethyl-4,4＂-bipyridinium][ZnX4] （X = CI （1） or Br （2）） with N-ethyl-4,4＂-bipyridinium generated in situ, have been synthesized through solvothermal reactions and structurally characterized by single-crystal X-ray diffraction analyses. Both compounds are isostructural and crystallize in the P2/c space group of monoclinic system. Compound 1： a = 8.4397（5）, b = 21.988（1）, c = 8.8777（5） А, β = 106.490（1）°, V = 1579.7（2） A3, C2H15C14N2Zn, Mr = 394.43, Z = 4, Dc = 1.658 g/cm3, S = 1.068,/a（MoKa） = 2.218 mm-1, F（000） = 796, R = 0.0295 and wR = 0.0766. Compound 2： a = 8.4154（6）, b = 22.844（2）, c = 9.0308（7） A, fl = 106.026（1）°, V = 1668.6（2） A3, Cj/HjsBraN2Zn, Mr = 572.27, Z = 4, Dc = 2.278 g/cm3, S = 1.033, /l（MoKa） = 11.038 mm＂1, F（000） = 1084, R = 0.0427 and wR = 0.1175. Both of them are characteristic of an isolated structure with the zinc atoms locating at a tetrahedral environment. In both compounds, the N-ethyl-4,4＂-bipyridinium2＋ cations and ZnX42- anions interconnect together via hydrogen bonding interactions to construct a three-dimensional （3-D） supramolecular framework. Fluorescent studies reveal that both compounds exhibit a strong emission in the green region. In combination with the theoretical calculations, we can draw a conclusion that the emissions should result from ligand-to- ligand charge-transfer （LLCT） transition.

NBO Population Analysis and Electronic Calculation of Four Azopyridine Ruthenium Complexes by DFT Method

The molecular structure, the Natural Bond orbital (NBO) and the Time Dependent-DFT of both isomers cis or γ-Cl and trans or δ-Cl of RuCl2(L)2, where L stands respectively for 2-phenylazopyridine (Azpy), 2,4-dimethyl-6-[phenylazo]pyridine (Dazpy), 2-[(3,5-dimethylphenyl)azopyridine] (Mazpy) and 2-pyridylazonaphtol (Nazpy) were calculated with DFT method at B3LYP/LANL2DZ level. The prediction of the frontier orbitals (Highest Occupied Molecular Orbital or HOMO and Lowest Unoccupied Molecular Orbital or LUMO) shows that the most active complexes suitable for electronic reactions are admitted to be the trans isomers. Moreover, δ-RuCl2 (Azpy)2 is discovered to react more actively as photo-sensitizer since its energy gap is the minimum. Besides, electronic structures of all complexes through NBO calculation indicate that Ru-N bonds are made of delocalization of occupancies from lone pair orbital of N atoms to the ruthenium. Moreover, Ru was assumed to have almost the same charge regardless the structure of the azopyridine ligands in the complex indicating that the ligands provide only a steric effect that is responsible for the ruthenium’s selectivity. Concerning the transition state, NBO analysis also highlights that the transition LP(Ru) π*(N1-N2) does correspond to t2g?π*(L). This transition is assumed to correspond to Metal to Ligand Charge Transfer (MLCT) that is responsible for the photo-sensitiveness of the metallic complex. Besides, TDDFT calculation of complexes showed that δ-RuCl2(Nazpy)2 displays the largest band during the absorption. For that reason, it is admitted to be the best photosensitizer due to a large system of conjugation provided by Nazpy ligand.

一种2-甲基-3-羟基喹啉-4-甲酸单核铜(Ⅱ)配合物的合成、晶体结构、理论计算与性质（英文）

以2-甲基-3-羟基喹啉-4-甲酸和1,10-菲咯啉为原料,经溶剂热法合成了一种新颖的Cu(Ⅱ)配合物,[Cu(L)(Phen)(H_2O)]·CH_3OH(1,HL=2-甲基-3-羟基喹啉-4-甲酸,Phen=1,10-菲咯啉),并通过红外光谱、元素分析、单晶衍射、固态漫反射、光致发光及理论计算对其结构和性质进行了研究。单晶结构分析表明配合物1的晶体属于单斜晶系,P2_1/c空间群,是一种零维(0D)结构的单核体。固态光致发光表明其为蓝紫色光发射体。时间密度泛函理论(TDDFT)计算表明其发射归属于配体-配体电荷转移(LLCT)。固态漫反射测量显示该化合物存在1.91 eV的窄带能隙。

Preparation,Structure,Fluorescence,Semiconductor Properties and TDDFT Calculation of a Mononuclear Zinc Complex with Mixed Ligands

A novel zinc complex[ZnL(bipy)(H2O)]×H2O with mixed ligands of 3-hydroxy-2-methylquinoline-4-carboxylic acid(HL)and bipy(bipy=2,2'-bipyridine)was synthesized by solvothermal reaction and its crystal structure was determined by single-crystal X-ray diffraction technique.The title compound crystallizes in the orthorhombic system of Pbca space group,and exists as an isolated mononuclear complex.The intermolecular hydrogen bonds and strongπ…πstacking interactions form a three-dimensional(3-D)supramolecular network.Solid-state photoluminescence spectrum reveals that it shows an emission in the blue region of the light spectrum.Time-dependent density functional theory(TDDFT)calculations reveal that this emission can be attributed to ligand-to-ligand charge transfer(LLCT).Solid-state diffuse reflectance data show that there is a narrow optical band gap of 1.83 eV.

A Novel Proton Sensor with Luminescence and Color Signaling Based on Platinum(II) Terpyridyl Acetylide Complex

A novel sensitive probe for proton based on platinum(II) terpyridyl acetylide complex by monitoring the changes both in luminescence and color is described.