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In the wavelength range of 231-275 nm, we have studied the mass-resolved dissociation spectra of OCS+ via B2+←X23/2(000) and B2+←X21/2(000, 001) transitions by preparing OCS+ ions in the well-defined spin-orbit states. The spectroscopic constants ofυ1(CS stretch)=828.9 (810.4) cm-1, υ2(bend)=491.3 cm-1 and υ3(CO stretch)=1887.2 cm-1 for OCS+(B2+) are deduced. The observed dependence of the υ2(bend) mode excitation of B2+ on the spin-orbit splitting of X2∏(Ω=1/2, 3/2) in the B2+←X2∏ transition can be attributed to the K coupling between the (000)21/2 and (010)2+1/2 vibronic levels of X2∏ state, which makes the B2+(010)←X21/2(000) transition possible.  相似文献   

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谢安东  朱正和 《化学学报》2005,63(23):2126-2130
使用SAC/SAC-CI和D95++,6-311++g,6-311++g**及D95(d)基组,分别对BF分子的基态X1∑+、第一简并激发态A1∏和第二激发态B1∑+的平衡结构和谐振频率进行优化计算.对所有计算结果进行比较,得出6-311++g**基组为最优基组.运用6-311++g**基组和SAC方法对基态X1∑+,SAC-CI方法对激发态A1∏和B1∑+进行单点能扫描计算,并用正规方程组拟合Murrell-Sorbie函数,得到相应电子态的势能函数解析式,由得到的势能函数计算了与X1∑+,A1∏和B1∑+态相对应的光谱常数,结果与实验数据较为一致.  相似文献   

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A novel compound, [MnPhen3][(B9C2H11)Co(B8C2H10)Co(B9C2H11)]· CH3CN (Phen = 1,10-phenantroline), comprising a Co(III) dicobaltacarborane cluster anion has been prepared and characterized by single crystal X-ray diffraction. Crystal data are the following: C44H59B26N7Co2Mn, M = 1139.84, triclinic, space group , unit cell parameters: a = 13.2465(11) Å, b = 14.521(2) Å, c = 15.2536(15) Å; α = 77.027(9)°, β = 88.500(8)°, γ = 77.274(9)°; V = 2788.5(5) Å3, Z = 2, d calc = 1.358 g/cm3, T = 295 K, F(000) = 1162, μ = 0.853 mm−1. The structure was solved by the direct and Fourier methods and refined anisotropically (isotropically for hydrogen atoms) using the full-matrix technique to final factors R 1 = 0.0374, wR 2 = 0.0915 for 7397 I hkl ≥2σI of 9779 I hkl measured (diffractometer Enraf-Nonius CAD-4, λMoK α , graphite monochromator, θ/2θ-scanning). The structure is formed from [MnPhen3]2+ cations, [(B9C2H11)×Co(B8C2H10)Co(B9C2H11)]2− anions, and acetonitrile molecules CH3CN. Central Mn atom in the cation has a distorted octahedral coordination environment formed by six nitrogen atoms of three bi-dentate Phen ligands, average Mn-N bond length being 2.263(2) Å. The anion has a chain-like structure built from three icosahedra sharing common vertices occupied by the cobalt atoms. The central icosahedron including ten light atoms (8B, 2C) provides two vertices for the cobalt atoms shared with the other icosahedra having 11 light atoms (9B, 2C). The arrangement of-C2-groups in the anion corresponds to a quasi-gauche-configuration of asymmetric sandwich complexes of both cobalt atoms. Original Russian Text Copyright ? 2005 by T. M. Polyanskaya, V. V. Volkov, and M. K. Drozdova __________ Translated from Zhurnal Strukturnoi Khimii, Vol. 46, No. 4, pp.730–740, July–August, 2005.  相似文献   

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谢安东  朱正和 《化学学报》2005,63(23):2126-2130
使用SAC/SAC-CI和D95++, 6-311++g, 6-311++g**及D95(d)基组, 分别对BF分子的基态X1Σ、第一简并激发态A1Π和第二激发态B1Σ的平衡结构和谐振频率进行优化计算. 对所有计算结果进行比较, 得出6-311++g**基组为最优基组. 运用6-311++g**基组和SAC方法对基态X1Σ, SAC-CI方法对激发态A1Π和B1Σ进行单点能扫描计算, 并用正规方程组拟合Murrell-Sorbie函数, 得到相应电子态的势能函数解析式, 由得到的势能函数计算了与X1Σ, A1Π和B1Σ态相对应的光谱常数, 结果与实验数据较为一致.  相似文献   

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Zusammenfassung Es wurde die ionophoretische Trennung von ReCl6 2–, ReBr6 2– und ReO4 unter Verwendung verschiedener Papiersorten untersucht. Am geeignetsten erwies sich das Papier 2045 b Gl von Schl. & Sch.
Summary The ionophoretic separation of ReCl6 2–, ReBr6 2–, and ReO4 has been examined using different kinds of paper. Best results have been obtained with the paper 2045 b Gl from Schleicher & Schüll.


Herrn Prof. G. Brauer danke ich für Förderung. Für die Überlassung von Rheniumverbindungen bin ich der Fa. W. C. Heraeus, Hanau, verpflichtet. Die Neutronenaktivierung wurde freundlicherweise von den Herren Dr. Marth und Dr. Köhler von der Reaktorstation in Garching bei München vorgenommen. Das Bundesministerium für Atomkernenergie und Wasserwirtschaft unterstützte die Untersuchung durch eine Sachbeihilfe.  相似文献   

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邓渝 《无机化学学报》1990,6(1):112-115
从卤水、海水中提取Li是目前较为活跃的研究课题。用液膜法从Li~+、Na~+、K~+混合溶液中分离Li~+的报道很少。协同效应在乳状液型液膜中的应用还未见报道。本文采用噻吩甲酰三氟丙酮(HTTA)和磷酸三丁酯(TBP)作为混合载体的液膜体系,快速、高效地从Li~+、Na~+、K~+的混合溶液中分离、浓缩Li~+,为从卤水、海水中提取Li~+提供了重要的依据。  相似文献   

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通过高温固相反应合成了La1/3NbO3∶Sm3+荧光粉.样品的荧光光谱表明,La1/3NbO3∶Sm3+荧光粉最强的激发带在406 nm,对应于Sm3+的6H5/2→4K11/2跃迁,属于近紫外区(365~410 nm).当激发波长为406nm时,样品的最强发射峰位于596 nm,是由Sm3+的4G5/2→6H7/2跃迁而产生的.因此,La1/3NbO3∶Sm3+可以作为基于近紫外激发的白光发光二极管(LED)的红光材料.而且,La位共掺杂Sr2+,Ba2+和Bi3+使样品的荧光强度大大增加,在最佳掺杂浓度时的量子产率分别为5.4%,7.5%和5.3%.  相似文献   

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通过对Fe3+/Ba2+/Co2+/Zn2+/Cu2+在NH4HCO3-NH3·H2O和NaOH-Na2CO3体系中的热力学分析,得到各金属离子总浓度(cMe)与pH值的关系,确定了2种体系中5种离子完全共沉淀的pH值范围.结果表明:在NH4HCO3-NH3·H2O体系中,Co2+、Zn2+、Cu2+3种离子和氨的配位能力很强,其中Cu2+与氨的配位能力最强,在相同的pH值条件下,Cu2+沉淀困难,5种金属离子的完全共沉淀区域由Cu2+决定.在NaOH-Na2CO3体系中,随总碳浓度(cc)的增加,Ba、Co、Zn、Cu的溶解度都随之减小,当cc=1.0 mol·L-1时,各金属离子完全共沉淀的pH值范围为7.5~11.在两种体系中,Fe的溶解度都是随pH值的增大而减小,最终达到平衡.以NaOH-Na2CO3 为沉淀剂.在pH=10.0的条件下,采用化学共沉淀法合成出了晶粒细小、粒度均匀的Y型纯相结构的平面六角铁氧体微粉.  相似文献   

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王霞  胡辉  白燕 《无机化学学报》2013,29(4):659-664
采用水热法制备了发白光的Li+掺杂α-TeO2∶Tm3+/Er3+/Yb3+和β-TeO2∶Tm3+/Er3+/Yb3+纳米上转换发光材料。采用X射线衍射、透射电镜和上转换发光光谱对制备的TeO2∶Tm3+/Er3+/Yb3+/Li+纳米材料进行表征,结果显示:Li+的掺入基本不改变纳米材料的晶型和结构;在980 nm近红外光的激发下,纳米材料发射出中心波长476 nm的蓝光,525 nm及545 nm的绿光和659 nm及675nm的红光,分别对应于Tm3+的1G4→3H6能级跃迁,Er3+的2H11/2→4I15/2和4S3/2→4I15/2能级跃迁,Er3+的4F9/2→4I15/2能级跃迁和Tm3+的3F2→3H6能级跃迁;Li+的掺入能够增大白光体系的发光强度,基本不改变纳米材料的白光颜色。此外,探讨了纳米材料的上转换发光机理。  相似文献   

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采用芳香族π共轭及含氮原子有机连接剂,合成同构铽、铕发光配位聚合物(CPs){[Eu(PLIA)1.5(H2O)2]·H2O}n (1)和{[Tb(PLIA)1.5(H2O)2]·H2O}n (2),其中H2PLIA=5-((吡啶-4-基甲基)氧基)苯-1,3-二甲酸。对合成的配合物进行了结构测定、表征和荧光痕量识别实验研究。2个同构配合物具有理想的三维框架结构,ππ堆积及氢键等弱相互作用增强了其化学稳定性;表征显示配位聚合物12具有良好的荧光性质、结晶性、热力学稳定性及结构完整性,可作为荧光传感的材料。12对水溶液中的Zr4+、Cr2O72-和Fe3+、HPO42-具有选择性好、灵敏度高的荧光识别能力,其检出限分别为0.139 μmol·L-1(1,Zr4+)、0.626 μmol·L-1(1,Cr2O72-)、0.430 μmol·L-1(2,Fe3+)、1.36 μmol·L-1(2,HPO42-)。探究了12作为探针的荧光猝灭机理。更有趣的是,12具有指纹识别性能,其荧光指纹纹路清晰连贯,细节明显,可被清晰观察。  相似文献   

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采用等温溶解平衡法研究了五元体系Na, K, Mg2+//Cl, NO3-H2O在298.16 K、氯化钠饱和时各盐的溶解度和饱和溶液的物化性质(密度, 电导率)以及四元体系Na, Mg2+//Cl, NO3-H2O的相平衡关系. 研究表明: 在298.16 K, 氯化钠饱和时该五元体系溶解度相图由六个结晶区、九条单变量溶解度曲线和四个零变量点构成, 六个结晶区分别对应于NaNO3+NaCl, KNO3+NaCl, KCl+NaCl, Mg(NO3)2•6H2O+NaCl, MgCl2•6H2O+NaCl和复盐KCl•MgCl2•6H2O+NaCl; 在298.16 K时, 该四元体系的相图由四个结晶区、五条单变量溶解度曲线和二个零变量点构成, 四个结晶区分别对应于NaNO3, NaCl, Mg(NO3)2•6H2O, MgCl2•6H2O.  相似文献   

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Zusammenfassung Es wird über eine Methode zur Bestimmung von Halogenidionen in Halogenidgemischen berichtet. Die Endpunktindikation erfolgt nach dem Prinzip der Polarisationsspannungstitration und liefert scharf ausgeprägte Titrationsendpunkte in der Reihenfolge der Schwerlöslichkeit der Ag-Halogenide. Insbesondere wird auch der für Serienanalysen erforderlichen Einfachheit und geringen Störanfälligkeit Rechnung getragen. Das Verfahren eignet sich für die Analyse anorganischer Halogenidgemische, für die Bestimmung von CN- und SCN -Ionen und für die Analyse organischer Halogenverbindungen im Makro- und Halbmikromaßstab nach deren Aufschluß. Die Meßanordnung kann außerdem für die Bestimmung von Kalium und für die Endpunktindikation einiger chelatometrischer Titrationen eingesetzt werden.
Summary A method is described for the determination of halogenide in mixtures of halogenides. End points are sharply indicated by the polarisation titration technique in the order of solubility of the silver halogenides. The method is suitable for the analysis of mixtures of inorganic halogenides, for the determination of CN and SCNions, and for the analysis of organic halogen compounds in macro and semimicro scale after decomposition. For routine analyses it offers the advantage of being simple and only slightly liable to interferences. Moreover, the assembly can be used for the determination of potassium and for the end point indication in some chelatometric titrations.
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采用"扶手椅"型碳纳米管建立了连续的碳纳米管膜模型,利用分子动力学模拟方法研究了Li+和Mg2+在膜中的传导行为.模拟研究了不同管径的碳纳米管CNTs(7,7),(8,8),(9,9),(10,10),(11,11)对Li+和Mg2+的通透性,检测了两种离子进入管内时的平均力势,探索了两种离子在碳纳米管内的径向、轴向密度分布,观测了个别离子在管内的运动轨迹.结果表明,模拟中CNTs(9,9)用于有效分离Li+和Mg2+的效果较好.管径不同,导致Li+和Mg2+通量不同,平均力势(PMF)差值不同,同时离子的轨迹和径向、轴向密度分布也有所差异.总之,碳纳米管是一种可将Li+和Mg2+分离的潜在材料.  相似文献   

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The absorption spectrum of N2+ has been studied using optical-heterodyne velocity mod-ulation spectroscopy in the near-infrared region. The observed spectral lines were assigned to the (3,1), (4,2), (5,3), (8,5) bands of the A2Πu-X2Σ+g system and the line lists were provided. The (5,3) band was studied for the first time. Fourteen rotational-resolved bands in literatures were fitted together with our observed bands and the molecular constants were obtained for υA=0-9 and υX=0-5.  相似文献   

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Lithium and silicon have the capability to form hypervalent structures, such as Li3 and SiH5, which is contrasted by the absence of this capability in hydrogen and carbon, as exemplified by H3 and CH5 which, although isoelectronic to the former two species, have a distortive, bond-localizing propensity. This well-known fact is nicely confirmed in our DFT study at BP86/TZ2P. We furthermore show that the hypervalence of Li and Si neither originates from the availability of low-energy 2p and 3d AOs, respectively, nor from differences in the bonding pattern of the valence molecular orbitals; there is, in all cases, a 3-center-4-electron bond in the axial X–A–X unit. Instead, we find that the discriminating factor is the smaller effective size of C compared to the larger Si atom, and the resulting lack of space around the former. Interestingly, a similar steric mechanism is responsible for the difference in bonding capabilities between H and the effectively larger Li atom. This is so, despite the fact that the substituents in the corresponding symmetric and linear dicoordinate H3 and Li3 are on opposite sides of the central atom. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.
F. Matthias BickelhauptEmail:
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