利用XPS研究Y-Ba-Cu-O超导体**(Ⅰ)

实验部分XPS数据来自英国VG公司ESCA LAB-5型电子能谱仪,对谱仪能量标度及样品荷电位移的校准,皆以文献的标准数据为准,为了使光电子峰具有较好的分辨卒,以及尽量避开俄歇峰的重叠干扰,本实验主要采用MgKα_(1,2)辐射。     

用 X-射线光电子能谱对钇的配位化合物的研究——Ⅱ.轫致辐射诱导的钇俄歇谱

利用轫致辐射诱导的俄歇谱,对约在1737eV处高动能的YL_3M_(45) M_(45)俄歇峰进行研究,发现它与钇的价态有一定关系。在通常的铝靶上,提供既可记录特征光电子峰,又能测量高动能的俄歇峰的方法。     

XPS分析绝缘样品中磁透镜对中和效果的影响研究

以绝缘样品聚对苯二甲酸乙二醇酯(PET)为X射线光电子能谱(XPS)分析测试对象,探讨了使用不同的X射线源作为激发源时,磁透镜对荷电中和系统中和效果的影响.试验结果表明,当使用单色化Al Kα为激发源时,磁透镜对荷电中和器的中和效果没有显著影响.而使用非单色化双阳极Mg Kα为激发源,磁透镜开启时才能得到良好的荷电中和效果,磁透镜关闭时所测谱峰会因荷电效应而发生峰形畸变.     

2—乙烯吡啶—丁烯酮共聚物及其羰基铑配合物的XPS研究

本文用X-射线光电子能谱(XPS)研究了2-乙烯吡啶-丁烯酮共聚物及其与四羰基二氯二铑形成的配合物的结构特征.由反映在共聚物Cls光电子伴峰和(?)基Cls峰的消失,以及共聚物Nls和Ols结合能在配合物中的降低,即从施受两方面确证N→Rh和O→Rh配位键的形成.对催化性能的探讨表明,丁烯酮含量的增加导致催化活性的升高,这是由于O→Rh配位键比例的增加和键强较弱所致     

磁透镜引起的氯化银谱峰异常位移及其在X射线光电子能谱成象分析中的应用

用X射线光电子能谱（XPS）分析了与样品托有良好电接触的银片及其上面的AgCl。观察到在使用样品磁透镜和非单色化X射线源的实验条件下不导电的AgCl的电子峰产生异常大的谱峰位移,还发现这种异常谱峰位移可以应用于XPS成象分析,以提高化学位移很小的元素化学态（如Ag^0和Ag^ )的XPS象的分辨能力。     

杂多酸PMo_(12-x)V_x和PMo_(12-x)W_x的XPS研究 Ⅱ.氧的双电离能及轫致辐射诱导的磷、钼俄歇谱

利用式E_Ⅱ(min)=E_B(K)-E_i(L_(23)~ L_(23)~ )可以从OKL_(23)L_(23)价态型俄歇跃迁能量求出氧的双电离能,它与杂多酸的Bronsted质子酸有一定的对应关系。本文利用铝靶的轫致辐射诱导MoL_3M_(45)M_(45)和PKL_(23)L_(23)俄歇跃迁,实现了在一个阳极和同一次实验情况下,既测得Mo、P特征的电光电子峰,又记录了高动能的俄歇峰。Mo、P的俄歇谱可表明杂原子与杂多配位原子的关系。     

样品磁透镜对绝缘样品XPS分析的影响

用XPS分析绝缘样品时, 启用样品磁透镜有可能引起谱峰位移和峰形畸变,其原因是磁透镜的磁场与双阳极铝窗发出的低能电子发生了相互作用,并使后者偏转,从而影响了到达样品表面起中和作用的低能电子的数量和分布.实验显示, 用与不用磁透镜所造成的谱峰差异, 有可能被用来研究绝缘样品的光导现象.     

样品高度对XPS测试的影响

采用Al靶微聚焦单色器光电子能谱仪进行XPS测试时,如果样品高度选择不好,会导致测得的光电子峰强度降低. 而对于一些电子结合能较高的元素,其光电子峰会变宽,有时出现双峰. 分析了该现象的原因是X射线光斑、电子中和枪中和区域以及光电子能量接收区域没有聚焦于同一点.     

样品表面污染对X射线光电子能谱定量分析的影响

用X射线光电子能谱(XPS)研究了表面碳污染物对样品的元素相对定量误差的影响。结果表明,样品表面含有碳污染物能引起光电子动能较低的元素的相对定量分析结果偏低,而且样品中两种元素的光电子动能差越大,相对误差越大。在用元素灵敏因子法进行XPS定量分析时,样品表面污染是不可忽略的误差来源。     

XPS光电子峰和俄歇电子峰峰位表

在长期从事XPS分析测试的经验基础上,搜集了有关文献中的大量数据,编制了XPS光电子峰和俄歇电子峰峰位表,用于正确识别各种样品XPS谱图中的电子峰,达到快速、正确分析各种样品元素组成和化学组成的目的．本峰位表对于从事XPS测试的分析人员和应用XPS的科技人员具有很好的实用价值．     

Photoelectron spectroscopy of phenyldihalophosphites

In order to explain the reactivity of aryldihalophosphites towards halophosphomum salts, photoelectron spectra of PhOPX₂ (X=F, Cl) were studied. Electron densities of boundary molecular orbitals (MO) for these compounds were calculated using the MNDO method and analyzed. Replacement of F by Cl was shown to substantially affect the orbital. When X= Cl, this MO embraces the whole of the OPX₂ moiety whereas for X=F it is localized on the P-O bond.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 323–324, February, 1993.     

Photoelectron spectra of cyclopolysilanes

Summary He (I) PE spectra of cyclopentasilane and cyclohexasilane show excellent agreement with STO-3 G + ab initio calculations. The HOMO in both compounds is of (SiSi) 3 p character. First IP's appear at 9.4 and 9.6 eV respectively.

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Photoelektronenspektren von Cyclopolysilanen (Kurze Mitt.)

Zusammenfassung Die He (I) PE-Spektren der Cyclosilane Si₅H₁₀ und Si₆H₁₂ zeigen ausgezeichnete Übereinstimmung mit STO-3 G + ab initio Rechnungen. Beide Ringe besitzen HOMO's mit (SiSi) 3 p Charakter. Die ersten Ionisierungspotentiale liegen bei 9.4 bzw. 9.6 eV.

     

Photoelectron spectrum of tetraiodomethane

The Hel photoelectron spectrum of tetraiodomethane Cl₄ is reported and assigned on the basis of empirical arguments Spin-orbit and Jahn-Teller splittings up to 1.6 and 0.32 eV, respectively, are observed in some systems.     

The Photoelectron Spectrum of Tetrafluorobutatriene

The He(I_α) and He(II_α) spectra of tetrafluorobutatriene 3 (F) have been recorded for comparison with those of butatriene 3 (H). Ab initio double-zeta basis self-consistent field (SCF) and configuration interaction calculations on butatriene show that, contrary to previous assignment, no shake-up band is expected to appear in the 9–10 eV energy range of the photoelectron spectrum. Further, such SCF calculations on tetrafluorobutatriene support the use of the perfluoro effect in assigning the purely π orbital ionizations. It is argued that 3 (F) is a key compound for the study of the perfluoro effect. This is supported by a qualitative comparison of its photoelectron-spectroscopic results with those of other perfluoro systems.     

Photoelectron Spectra of Vicinal Tricarbonyls

The He I photoelectron spectra of tetramethylcyclopentane-1,2,3-trione 1 , 4,4,6,6-tetramethylcyclohexane-1,2,3-trione 2 , bicyclo[1.2.3]octane-2,3,4-trione 3 , bicyclo[2.2.3]nonane-2,3,4-trione 4 and anhydrous ninhydrine 5 are presented. The assignment of the first two bands is discussed using semiempirical calculations together with a qualitative band shape analysis. It is shown that the first two bands in 1 to 4 are due to the ionization of an electron from lone pair combinations of the 2p-oxygen orbitals.     

Photoelectron spectra of 1,4-benzodiazepines

Photoelectron (PE) spectra of 20 biologically active molecules of 1,4-benzodiazepine derivatives have been measured. The spectra in the range of low ionization energies (IE) were interpreted by comparison of MNDO quantum-chemical calculation data with the perturbation theory estimations. The effect of substituents and structural changes in the series studied is felt mainly by the -MOs of ring A; theortho effect is observed in the PE spectra ofortho isomers.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1583–1587, September, 1993.     

Photoelectron spectra of substituted benzenes

Photoelectron spectra of several substituted dimethylanilines, nitrobenzenes, acetophenones and nitrosobenzenes have been studied with a view to examine the electronic effects of substituents on the various φ and n levels. The results are discussed in the light of molecular orbital calculations and electronic absorption spectra. Correlation of substituent effects on the IE's with π-electron densities and Hammett substituent constants has enabled rationalization of all available data on mono- and disubstituted benzenes. The IE's generally increase with the electron-withdrawing power of the substituents.     

Analytical Aspects of Photoelectron Spectroscopy

Photoelectron spectroscopy is a new technique for experimentally measuring the binding energies of electrons in molecules. The basic principles of the method are outlined and simple guidelines for the interpretation of u.v.-excited photoelectron spectra are laid down. The analytical potential and possible development of the method are briefly surveyed.