Spectroscopic and Structural Studies of Complex of [CU(DIEN)(CNGE)(ONO2)2] (Dien=Diethylenetriamine,CNGE=Cyanoguanid)

The electronic absorption spectrum (diffuse reflection spectrum) of the crystal of [Cu(dien)(cnge)(ONO₂)₂] has been measured. The experimental results are interpreted quantitatively with ligand field theory and the radial wave function of non-free copper (II), and our calculation values coincide well with the experimental results. As a result, the d-d absorption spectrum was explained satisfactorily. In particular, the structural characterizations whose degree of distortion of crystal structures of three Copper(II) complexes is different in this paper, are also discussed with their spectral behaviors. The experimental data provides significant correlation between the spectra and degree of distortion of coordination structures.     

The Crystal Structure of Platyphylline and Molecular Conformational Analysis of Integerrimine

The title compounds platyphylline (C₁₈H₂₉NO₅.0.5H₂O) and integerrimine (C₁₈H₂₅NO₆) have been isolated from the serial parts of the Senecio species. the crystal and molecular structures of platyphylline have been determined. the compound crystallises in orthorhombic space group, P2₁2₁2₁. the pyrrolizidine nucleus exhibits exo-buckling conformation. the molecular geometry was stabilized by C-H[ddot]O and C-H[ddot]N hydrogen bonds. a search for the low energy conformations of integerrimine as a similar alkaloid was also carried out. Force field calculations were undertaken by the MM3 program and some particular conformations were computed with the semi-emprical molecular orbital methods by the AMI and PM3 programs.     

REE Spectral Lines for the Determination of Excitation Temperature in Analytical Plasmas

The spectra of rare earth elements (REE) have been investigated to select thermometric species for spectroscopic diagnostic of analytical plasmas. Groups of lines of Y II, La II, Eu II and Yb II were found appropriate for the determination of ionic excitation temperature in argon wall-stabilized plasma arc (WSA) and inductively coupled plasma (ICP). Boltzman plots with excellent Fitting to straight lines were obtained. Temperature values deduced with the different groups of spectral lines agree with each other as well as with that obtained with the most familiarly used Ti II lines.

     

Spectra,Magnetic Property and Coordination Structure Study on Polymeric Copper(II) Iodo Complex of Diethylenetriamne

Abstract

Polymeric [Cu(dien)Ix] (dien = diethylenetriamine) was prepared. Its electronic absorption spectrum and photoacoustic spectrum were recorded at room temperature. They were compared with each other and the results were discussed quantitatively with respect to ligand field theory (LFT) and the radical scaling wave function of a non-free copper(II) ion. The theoretical values are in agreement with the observed ones. In addition. the ESR spectra of the title complex were measured at 77k and room temperature, respectively. They were compared with each other and characterized. Therefore, the electronic structure was also investigated with its spectra behaviors and PLFT. The spectra and the theoretical analysis about the title complex suggest there is a weak interaction between the Cu-Cu. It can be interpreted with using Kahn's theory. The g (= 2.0942) is greater than 2.040, conforming to a ground state configuration with unpaired electron in the dx²?y² orbital.     

邻菲啰啉和水杨酸构筑铜配合物的电化学行为及与DNA的相互作用

合成了一种新型的三元铜配合物[Cu(phen)(SA)_2]·H_2O(phen=1,10-邻菲啰啉,SA=水杨酸),并以鲱鱼精DNA为靶点,通过紫外吸收光谱法、循环伏安法、差分脉冲伏安法和DNA粘度滴定实验,探讨了配合物与DNA的键合方式。结果表明,SA的羧酸根离子与Cu~(2+)单齿配位,phen的两个氮原子与Cu~(2+)呈双齿配位,形成的配合物在0.489 V/0.050 V处呈现一对明显的准可逆氧化还原峰,并且中心Cu~(2+)在玻碳电极上的反应主要由扩散过程控制。配合物与DNA作用时,可观察到配合物的紫外光谱出现明显的减色效应,但是红移现象不明显,氧化还原峰的电流减小,峰电位发生正移,并且DNA的粘度随配合物的加入而增大。结论认为,配合物以嵌插方式与DNA发生作用形成1∶1的复合物,但插入程度较弱(结合常数为1.55×10~4L·mol~(-1))。     

Spectroscopic Study of the Interaction of Mitoxantrone with Copper(I), Copper(II), and Neocuproine

Both reductive and oxidatlve mode of metabolism have been hypothesized for the antitumor agent mitoxantrone. This work aims to better understand the redox properties of mitoxantrone in the presence of the physiological redox couple, copper(I)/copper(II), by means of polarograpy and spectrophotometry. The first quasi-reversible one-electron reduction of mitoxantrone to the semiquinone and the second reduction to the hydroquinone have been shown to be considerably affected by copper. Visible spectra of mitoxantrone-copper mixtures in nitrogen and oxygen purged solutions taken in a one-week period exhibit varying degrees of complexation and oxido-reduction.

When copper(II), neocuprolne and mitoxantrone are mixed in a certain ratio in pH 7. 4 phosphate buffer solution, two new peaks at 584 and 632 nm emerge in the spectra indicating a ternary charge transfer complex. The complex atoichiometry was established as Cu(IT): neocuproine: tritoxan-trone = 2:4:1 by Job's method of continuous variations. The ternary complex is sensitive to the relative concentrations of mitoxantrone and copper(II), an excess of the latter giving rise to complete red ox products. This complex may be important in modeling the drug's oxidative mode of ant tumor action.     

Trigonally-compressed octahedral geometry of hexaamminecobalt(III) complex cation in aqueous solution investigated from the electronic spectra

Electronic spectra of hexaamminecobalt(III) complex cation in aqueous solution were analyzed to obtain spectral components. Subsequently, based on the spectral components, the coordination geometry around the cobalt(III) ion was investigated, using the reverse angular overlap model method. The result indicates that the geometry is a trigonally compressed octahedron with the polar angle of 57.9?±?1.0° under D_3d symmetry, where the polar angle is the angle between the trigonal axis and the Co–N bond. From this angle, the top and side N–Co–N bond angles are calculated as 94.4° and 85.6°, respectively. The density functional theory computation supported this trigonally compressed structure in aqueous solution.     

PDT光敏剂HA在不同液相体系下的光谱特性研究

为了对候选光敏剂竹红菌甲素(HA)进行改性并保持其优异的敏化特性,对HA的光谱特性和激发态性质作了进一步的指认。系统研究了HA在不同液相体系下的吸收和荧光光谱,对指认HA的光谱和电子跃迁的机制提出了新的依据,结果表明,吸收带I产生于π-π*跃迁,吸收带Ⅱ和Ⅲ产生于P-π共轭所导致的L→aπ跃迁的电子振动结构;荧光发射带I和Ⅱ是产生于同一跃迁机制S1(L,aπ)→S0的正常荧光的振动结构。     

Aggregation and spectral properties of Mg(II) tetracarboxyphthalocyanine in aqueous solutions and solid xerogels

Based on spectroscopic studies of magnesium(II) tetracarboxyphthalocyanine molecules in liquid solutions, we have determined the role of the carboxyl groups and the aqueous medium during formation of associates. We have shown that the Q band of the associated form is split into two components of frequency separated by ∼250 cm⁻¹. The effect of the nature of the gel matrices on the spectral luminescence properties of magnesium(II) tetracarboxyphthalocyanine has been studied by incorporating the pigment into a series of xerogels differing in the chemical structure of the inorganic framework and the nanopore surface area. We discuss the reasons for the appearance of associated forms of the pigment in different xerogels. __________ Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 74, No. 2, pp. 211–217, March–April, 2007.     

RbNiCl_3晶体的局域结构、吸收光谱和顺磁g因子的统一解释

利用完全对角化方法和强场耦合方案,采用半自洽场(semi-SCF)自由Ni2 的d轨道模型,点电荷—偶极子模型和Ni2 -6X-(X=F,Cl,Br,I)络合物的μ-κ-α模型研究,建立了含有过渡族金属离子的晶体的局域结构与吸收光谱和顺磁g因子之间的定量关系,对RbNiCl3晶体的局域结构,吸收光谱和顺磁g因子作出了统一解释,所得理论计算结果与实验值符合得很好.这对进一步研究掺杂顺磁离子晶体的结构,光学,磁学,热学,电子顺磁共振参量,高压,精细结构等性质和了解晶体的结构信息提供了一种可行的方法.     

掺铥氟磷玻璃的结构、热学性质和光谱性质

制备了不同Al(PO3)3含量的掺铥系列氟磷玻璃,研究了其结构、热稳定性和光谱性质。随着Al(PO3)3含量的增加,该系列玻璃的密度降低,折射率增加,差热分析表明,转变温度、析晶起始温度、析晶峰温度和熔化温度增加。Al(PO3)3摩尔浓度在7%~9%时析晶稳定性最佳。采用归一化的拉曼光谱分析了材料的结构和声子状况,对于该系列氟磷玻璃,Al(PO3)3含量的增加不会影响声子能量,但使声子密度增大。测试了样品的吸收光谱,Tm3 的3H6→3F4在第三通信窗口的L波段有明显吸收。与在其它玻璃基质中相比,Tm3 的3F4能级对应能量偏高,3H4能级对应能量偏低,使得3H4→3F4跃迁波长较大,接近于增益迁移光纤放大器的放大波长。扎得奥菲而特(Judd-Ofelt)理论分析表明随着Al(PO3)3含量增加,离子强度参量Ω2增大,Ω6保持相对稳定,Tm3 的能级寿命降低。     

Synthesis and Spectroscopic Properties of Iron(H) Complex with Sterically Encumbered Thiolate Ligand: 2,4,6-Triphenylbenzenethiolate

Abstract

Novel iron(II) complex of 2,4,6-triphenylbenzenethiolate (tpbt) was synthesized by ligand exchange reaction of (Et₄N)2[Fe^II(S-t-Bu)₄] with tpbt-H. The complex shows absorption maxima at 277 nm (36500 M^?1cm^?1) and 367 nm (22800 M^?1 cm^?1), and Fe²⁺/Fe³⁺ redox potential at-0.78 V vs SCE in acetonitrile. While in tetrahydrofuran solution, the complex is found to be unstable and form a Fe(II) complex with low coordination number.     

Nd∶KY(WO4)2和Nd∶KG(WO4)2晶体吸收光谱性能分析

通过研究分析钨酸盐晶体Nd∶KY(WO₄)₂和Nd∶KG(WO₄)₂在室温下的吸收光谱，发现这2种晶体具有作为激光晶体的优良特性。根据Judd-Ofelt理论和测试所得的吸收光谱及数据，用VC++编程计算出晶体的谱线强度、振子强度、吸收截面等，拟合得Nd³⁺离子的3个晶场调节参数Ω_λ(λ=2，4，6)的值，并从理论上计算了自发跃迁几率、能级寿命、荧光分支比和积分发射截面。从计算得出的荧光分支比β可以看出，Nd∶KY(WO₄)₂(β_1060nm=0.4380)和Nd∶KG(WO₄)₂(β_1060nm=0.4618)晶体荧光分支比都较大，计算了该晶体的X=Ω₄/Ω₆，并将其X值与其他晶体的X值加以比较，Nd∶KY(WO₄)₂和Nd∶KG(WO₄)₂均易于实现1.06μm激光输出，适合作为LD泵浦的钨酸盐晶体激光器。     

Unified calculations of the optical and electron paramagnetic resonance spectral data for Ce ion in Y3Ga5O12 crystal

Seven crystal field energy levels (obtained from the optical spectra) and three g factors g_x, g_y and g_z (obtained from electron paramagnetic resonance (EPR) spectra) for Ce³⁺ ion in Y₃Ga₅O₁₂ crystal are calculated together by diagonalizing a complete energy matrix. The Hamiltonian of this energy matrix includes all the interactions for 4f¹ ion Ce³⁺ in rhombic crystal field and under an external magnetic field, and so the optical and EPR data can be studied in a unified way. The calculated crystal field energy levels are in better agreement with the experimental values than the calculated values in the previous paper, and the g factors (which have not been calculated previously) are explained reasonably. The results are discussed.     

Electronic structure and infrared spectrum of a WnC0＇± （n= 1-6） cluster

W_nC^0,± (n=1-6) clusters are investigated by using the density functional theory (DFT) at the B3LYP/LANL2DZ level. We find that the neutral, anionic and cationic ground state structures are similar within the same size, and constituted by substituting a C atom for one W atom in the structures of W_n+1 clusters. The natural bond orbital (NBO) charge analyses indicate that the direction of electron transfer is from the W atom to the 2p orbital of the C atom. In addition, the calculated infrared spectra of the W_nC^0,± (n=2-6) clusters manifest that the vibrational frequencies of neutral, anionic and cationic clusters are similar in a range of 80 cm^-1-864 cm^-1. The high frequency, strong peak modes are found to be an almost stretched deformation of the carbide atom. Finally, the polarizabilities of W_nC^0,± (n=1-6) clusters are also discussed.     

Surface chemistry and catalysis of oxide model catalysts from single crystals to nanocrystals

Fundamental understandings of surface chemistry and catalysis of solid catalysts are of great importance for the developments of efficient catalysts and corresponding catalytic processes, but have been remaining as a challenge due to the complex nature of heterogeneous catalysis. Model catalysts approach based on catalytic materials with uniform and well-defined surface structures is an effective strategy. Single crystals-based model catalysts have been successfully used for surface chemistry studies of solid catalysts, but encounter the so-called “materials gap” and “pressure gap” when applied for catalysis studies of solid catalysts. Recently catalytic nanocrystals with uniform and well-defined surface structures have emerged as a novel type of model catalysts whose surface chemistry and catalysis can be studied under the same operational reaction condition as working powder catalysts, and they are recognized as a novel type of model catalysts that can bridge the “materials gap” and “pressure gap” between single crystals-based model catalysts and powder catalysts. Herein we review recent progress of surface chemistry and catalysis of important oxide catalysts including CeO₂, TiO₂ and Cu₂O acquired by model catalysts from single crystals to nanocrystals with an aim at summarizing the commonalities and discussing the differences among model catalysts with complexities at different levels. Firstly, the complex nature of surface chemistry and catalysis of solid catalysts is briefly introduced. In the following sections, the model catalysts approach is described and surface chemistry and catalysis of CeO₂, TiO₂ and Cu₂O single crystal and nanocrystal model catalysts are reviewed. Finally, concluding remarks and future prospects are given on a comprehensive approach of model catalysts from single crystals to nanocrystals for the investigations of surface chemistry and catalysis of powder catalysts approaching the working conditions as closely as possible.