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1.
We use UV resonance Raman spectroscopy to probe the lowest energy allowed electronic transitions of aqueous solutions containing Cl(-) salts. We show that the waters hydrating the Cl(-) are involved in charge transfer transitions that transfer electron density from Cl(-) to the water molecules. These charge transfer transitions cause significant change in the H-O-H bond angle in the excited state, which results in a strong enhancement of the preresonance Raman intensity of the water bending modes. Our work gives the first insight into the lowest allowed electronic transition of hydrated Cl(-).  相似文献   

2.
New mixed complex compound bis(dibenzo-18-crown-6)(tetrachlorocuprato(II)-Cl, Cl′, Cl″, Cl?) dipotassium diaqua(dibenzo-18-crown-6)potassium dichlorocuprate(I)dibenzo-18-crown-6 [(CuCl4)[K(Db18C6)]2]·[K(Db18C6)(H2O)2]+·[CuCl2]?·Db18C6 was prepared and its structure was studied by the X-ray structural analysis. The structure was found to be disordered. The asymmetric part of its unit cell contains 1/4 of each of its four components. For a given [CuCl4]2? anion its Cu2+ cation is disordered over two equally probable positions and its independent Cl atom is disordered over three positions differing by occupancy. In this structure two [K(Db18C6)]+ fragment of the complex molecule and the complex cation [K(Db18C6)(H2O)2]+ are of guest-host type with K+ cation as the guest. In this structure the statistically disordered alternating cations and Db18C6 molecules form infinite chains. The statistically disordered [CuCl2]? anions also form infinite chains.  相似文献   

3.
The complex Re2Cl6(P-n-Bu3)2 prepared in situ reacts with CH3CN to form a blue-green solution. Addition of the chelating phosphine bis(diphenylphosphino)methane (dppm) results in the formation of the complex [Re2Cl3(-dppm)2(NCCH3)2][Cl] (1) upon heating. The two acetonitrile molecules adopt a trans geometry on the rhenium center with the axially coordinated chlorine. The analogous trans benzonitrile species [Re2Cl3(-dppm)2(NCC6H5)2][Cl]·2CH2Cl2 (2) is synthesized under the same reaction conditions. The coupling constants of the AABB 31P{1H} NMR spectra of the compounds were elucidated from 31P–31P homonuclear J-resolved NMR experiments. Additional characterization methods include 31P{1H} NMR spectroscopy, UV-vis spectroscopy, and X-ray crystallography.  相似文献   

4.
The anion coordination complex,[ClPt(bpt)4]Cl (bpt=N,N'-bis(3-pyridylmethyl)-2-thiourea),was synthesized and studied by X-ray crystal structure analysis,NMR and FAB mass spectra. In the solid state,the Pt(bpt)4 anion receptor adopts a cone conformation to bind the chloride anion through hydrogen bonds and electrostatic interaction in which the four branches of the thiourea ligands bind the chloride anion to form N-H…Cl-hydrogen bonds (3.49-3.81). The entraped chloride anion is situated above the Pt(Ⅱ) cen...  相似文献   

5.
Cl在Ag(111)上的吸附过程可分为三个变化阶段,即(a)—(c).本文运用AES,UPS,ISS以及功函数等表面科学手段研究了Cl的吸附行为,并着重分析了由(a)到(c)阶段时Cl吸附引起的表面物种变化及(c)阶段时Cl的存在状态.结果证明,(c)阶段时最表层上CI的浓度远小于一个单层,Cl向体相钻穿,钻穿深度至少大于40(?).  相似文献   

6.

The preparation, spectroscopic properties and crystal structure of (bis-imidazole)quinoline-copper(II) dichloride [Cu(Im)2(quin)Cl2] (Im = imidazole, quin = quinoline) and tetraimidazole-copper(II)-dichloride [Cu(Im)4Cl2] are reported. Both cocrystallize on the triclinic system, space group P-1, with cell constants a = 8.095(5) Å, b = 12.141(5) Å, c = 13.847(5) Å, α = 108.816(5)°, β = 104.173(5)°, γ = 94.965(5)° and Z = 2. In the [Cu(Im)2(quin)Cl2] complex the copper(II) ion is coordinated to two imidazole molecules, to one quinoline and two chlorine ions, with the copper(II) ion in a distorted trigonal bipyramidal coordination geometry. In the [Cu(Im)4Cl2] complex, the copper(II) ion has a distorted octahedral coordination geometry. The superoxide dismutase mimetic activity of the complexes was investigated using the indirect xanthine-xanthine oxidase-nitroblue tetrazolium method and compared to that of the native enzyme.  相似文献   

7.
本文应用停-流快速反应动力学测定仪器研究氯钼氧卟啉(MoVO(TPP)Cl)同二甲亚砜(DMSO)的反应动力学.实验结果表明,反应至少含有四个基元步骤.动力学研究得到驰豫时间τ与加入的初始二甲亚砜(DMSO)的浓度成线性关系,本文提出了一种反应机理,比较满意地解释了上述化学反应动力学实验结果。  相似文献   

8.
本文应用停-流快速反应动力学测定仪器研究氯钼氧卟啉(MoVO(TPP)Cl)同二甲亚砜(DMSO)的反应动力学. 实验结果表明, 反应至少含有四个基元步骤. 动力学研究得到驰豫时间τ与加入的初始二甲亚砜(DMSO)的浓度成线性关系, 本文提出了一种反应机理, 比较满意地解释了上述化学反应动力学实验结果。  相似文献   

9.
Photochromic ormosil coatings containing Ag(Cl1–x Br x ) microcrystals were formed on a glass substrate via the sol-gel process. Methyltrimethoxysilane and 3-glycidoxypropyltrimethoxysilane were used as starting materials of the ormosil matrices. 3-chloropropyltrimethoxysilane and bromophenyltrimethoxysilane were added as halogen sources and silver colloidal dispersion was introduced into the precursor sol. The coated glass became transparent and photosensitive after Ag(Cl1–x Br x ) microcrystals were precipitated in the coatings above 300°C. Insertion of a SiO2 buffer layer between the substrate and photochromic layer was effective in preventing Ag+ migration into the substrate. Photochromic performances were improved by the substitution of Cl with Br and the incorporation of a minute amount of Cu.  相似文献   

10.
用Si(CH_3)_3C1处理Y型沸石时,选择合宜的处理条件可获得高结晶度的产物。XRD,IR,比表面和孔径分布测定表明:用Si(CH_3)_3C1处理沸石,脱铝和硅烷化作用同时发生,导致沸石比表面和孔径改变,催化反应性能提高。  相似文献   

11.
Treatment of platinum(II) diamine [Pt(N,N-DimeTm)Cl2] (I) with pyridine gave tetramine [Pt(N,N-DimeTm)Py2]Cl2 (II); by oxidation with chlorine this was converted to Pt(IV) triamine, [Pt“(N,N-DimeTm(Py)Cl3]Cl (III) with a six-membered chelate ring. According to X-ray diffraction data, the reaction of complex II with chlorine is accompanied by removal of the pyridine molecule from the trans-position to the NH2 group of N,N-dimethyltrimethylenediamine. The reaction of complex III with chlorine at 20°C afforded a mixture of compounds (IV) and the complex [Pt“(CH3)2N(CH2)2C(O)NH”(Py)Cl3] (V) with an amidate six-membered metal ring, dimethylpropioamide, which was also isolated upon refluxing a mixture of IV in an aqueous solution. The UV/Vis and IR spectra of the obtained complexes were studied, and X-ray diffraction analysis of I, III, and V was performed. The crystals of I are triclinic, space group P $ \bar 1 $ ; a = 7.6526(4) Å, b = 11.5571(6) Å, c = 12.4432(7) Å, α = 113.85(1)°, β = 96.54(2)°, γ = 106.78(2)°; Z = 4; R hkl = 0.051. The crystals of III are monoclinic, space group C2/c; a = 36.715(2) Å, b = 7.8179(4) Å, c = 29.721(16) Å, β = 127.80(1)°; Z = 16; R hkl = 0.036. The crystals of V are monoclinic, space group P21/n; a = 7.0398(6) Å, b = 27.458(2) Å, c = 7.687(6) Å, β = 106.270(1)°; Z = 4; R hkl = 0.052.  相似文献   

12.
氯化钴;二甲氧基嘧啶胺;固态配合物;Co(AMP)2Cl2的合成及表征  相似文献   

13.
考察了Ag(111)表面和吸氯的Ag(111)表面上氧的吸附行为.结果表明在Ag(111)及低暴露量氯吸附的Ag(111)上氧吸附时,表面上均存在弱的分子氧和原子氧物种.但在高暴露量氯吸附的Ag(111)表面上氧吸附时则选择性地只产生表面分子氧物种,这种选择性只与氯的吸附程度有关,而与氯的存在与否无关.结合以前的实验结果,对氯吸附至(c)阶段时的Ag(111)表面上氧的选择性吸附行为的本质作了详细讨论.  相似文献   

14.
《Solid State Sciences》2003,5(1):183-188
A new imido-bridged tantalum compound, (NH4)3[{Ta2(NH)3Cl6}Cl], was synthesized from the mixture of TaCl5, NaNH2 and NH4Cl (excess) in a vacuum sealed silica tube at 350–400 °C. Single crystal X-ray diffraction results for the title compound detailed in the orthorhombic space group Cmcm (No. 63); Z=4, a=10.1601(6) Å; b=19.8834(13) Å; and c=7.4362(4) Å. The structure consists of imido-bridged one-dimensional chains with composition [Ta2(NH)3Cl6]2− and running along c. These chains are separated by ammonium and chloride ions. In the present study, NH4Cl was used to facilitate relatively smooth reaction between TaCl5 and NaNH2, which otherwise leads to an exothermic, self-propagating reaction.  相似文献   

15.
We test several binning techniques to obtain mode-specific final-state distributions for polyatomic reactions. Normal mode analysis is done after an exact transformation to the Eckart frame. Standard histogram binning (HB) and three different variants of the energy-based Gaussian binning (1GB) are employed to obtain the probabilities of the vibrational states. We consider the two major issues of the polyatomic quasiclassical product analysis, i.e., (1) rounding the classical action to the nearest integer can result in unphysical states and (2) the normal-mode analysis can break down for highly distorted geometries. We show that 1GB can handle issue 1 when the total vibrational energy is evaluated in the normal mode space using the harmonic approximation and both issues 1 and 2 can be solved when the total vibrational energy is calculated exactly in the Cartesian space. We found that anharmonicity in the quantized energy levels does not have a significant effect on the final-state distributions. Quasiclassical trajectory calculations are performed for the reactant ground-state and bending-excited Cl((2)P(3/2)) + CH(4)(v(4/2) = 0, 1) → H + CH(3)Cl reactions using an ab initio potential energy surface. The product analysis techniques are successfully applied to the CH(3)Cl product molecules and some qualitative features of the results are discussed.  相似文献   

16.
钌卟啉[Ru(bpy)2(MPyTPP)Cl]+与DNA作用的研究   总被引:4,自引:0,他引:4  
钌卟啉(ruthenated porphyrin)是通过卟啉环上的配位基团与多吡啶钌配位而得到的一类具有丰富的光谱和化学活性的大分子配合物[1~5]. 目前, 对钌卟啉的研究大都集中在其氧化还原、电化学以及催化氧化反应活性和超分子自组装等方面, 而对钌卟啉生物功能方面的研究则鲜为报道[6].  相似文献   

17.
The kinetics and mechanism of substitution reactions of novel monofunctional [Pt(tpdm)Cl](+) and [Pd(tpdm)Cl](+) complexes (where tpdm = tripyridinedimethane) and their aqua analogues with thiourea (tu), L-methionine (L-met), glutathione (GSH), and guanosine-5'-monophosphate (5'-GMP) were studied in 0.1 M NaClO(4) at pH = 2.5 (in the presence of 10 mM NaCl for reactions of the chlorido complexes). The reactivity of the investigated nucleophiles follows the order tu > l-met > GSH > 5'-GMP. The reported rate constants showed the higher reactivity of the Pd(II) complexes as well as the higher reactivity of the aqua complex than the corresponding chlorido complex. The negative values reported for the activation entropy as well as the activation volume confirmed an associative substitution mode. In addition, the molecular and crystal structure of [Pt(tpdm)Cl]Cl was determined by X-ray crystallography. The compound crystallizes in a monoclinic space group C2/c with two independent molecules of the complex and unit cell dimensions of a = 38.303(2) ?, b = 9.2555(5) ?, c = 27.586(2) ?, β = 133.573(1)°, and V = 7058.3(8) ?(3). The cationic complex [Pt(tpdm)Cl](+) exhibits square-planar coordination around the Pt(II) center. The lability of the [Pt(tpdm)Cl](+) complex is orders of magnitude lower than that of [Pt(terpyridine)Cl](+). Quantum chemical calculations were performed on the [Pt(tpdm)Cl](+) and [Pt(terpyridine)Cl](+) complexes and their reactions with thiourea. Theoretical computations for the corresponding Ni(II) complexes clearly demonstrated that π-back-bonding properties of the terpyridine chelate can account for acceleration of the nucleophilic substitution process as compared to the tpdm chelate, where introduction of two methylene groups prevents such an effective π-back bonding.  相似文献   

18.
PreparahonofsomecomplexcomPOundsof[Pd(NH3)41X2tw,tvhereX=Cl-,Br,I-,X2=Co,:-,RdChl'-,etc.,wasdescribedasearlyl942l'].SynthesisandcryStalstIUCtUreOfthesaltSt'ithamons,Cr2o7",Cro.:',MoO"',andC,o'=',ttcrestillreportedmorcrecenh/'-'j.IPd(NH)4lX2,tvhereX=Cl',BrandNOz,isanotherkindofamndnepalladiumcomplexcompounds.IntheSyStemofIPd(NH).1"-Cl'-H2o,diamlltinedichloridepalladium(II)wasObtalnedbythereachonOfIPd(NH)4lHcomplexionwtthanutebydrogenchloride,andtetrachloridepalladiumaDbythe…  相似文献   

19.
Nd(O-i-C3H7)2Cl可作为Ziegler-Natta催化剂中的主要成分用于共扼双烯的定向 聚合[1],其常用合成方法[1]需添加CH3COCl: 我们在实验中发现,Nd(O-i-C3H7)2Cl和异丙醇形成的络合物在苯-异丙醇混合溶液中并不沉淀析出,从而可用NdCl3·3HO-i-C3H7,和NaO-i-C3H7,直接合成Nd(O-i-C3H7)2Cl。  相似文献   

20.
1977年,Bradley等人报道了稀土离子间以双氧离子(O_2~(2-))为桥的稀土金属有机配合物的合成及其晶体结构,类似的稀土离子间夹有氧离子(O~(2-))的金属有机配合物也相继有些报道,但本文提出的含有六个Sm~(3+)夹有两个氧离子的簇状配合物则未见报道。  相似文献   

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