关于电子自旋的实验验证和理论思考

本文从斯特恩──盖拉赫实验证实电子具有自旋入手,用电子“自旋──轨道耦合”直观地解释了光谱线精细结构的双重线。     

Accounting for the Adsorption of Anions When Interpreting the Mechanism of Electrodeposition of Metals from Complex Electrolytes: The Reaction Order by the Electrochemically Active Ion

The relationship between the current and the bulk concentration of complex ions during concurrent specific adsorption of an electrochemically active complex ion and a complexing ligand is considered. The effect of parameters that characterize adsorption of such ions and the structure of the electrical double layer on this relationship is analyzed.__________Translated from Elektrokhimiya, Vol. 41, No. 7, 2005, pp. 817–822.Original Russian Text Copyright © 2005 by Rogozhnikov.     

Inner shell structure of heavy atoms

The inner-shell structure of some heavy atoms is examined using a self-consistent relativistic local density method. Ar(K), Kr(K) and Xe (K,L ₁,L ₂ andL ₃) binding energies and {ie863-1} (hyper-satellite) energies of Tl, Hg and Tm are calculated. The results are compared with available experimental data. A part of this work was presented byMPD at the Trieste International Symposium on “Core level excitations in atoms, molecules and solids,” 22–26 June 1981, Extended Abstracts (ed.) E Tosatti, ICTP Report No. 89/81 p. 11.     

Synthesis and Characterization of PE-g-MA/MgAl-LDH Exfoliation Nanocomposite via Solution Intercalation

Anorgano modifiedMgAl layereddoublehydroxide (OMgAl LDH )wassuccessfullyexfoliatedinthexylenesolutionofpolyethylene grafted maleicanhydride (PE g MA )underre fluxingcondition .APE g MA/MgAl LDHexfoliationnano compositewasformedaftertheprecipitationofPE g MAfromthedispersionsystem .ThestructureandthermalpropertyofthePE g MA/MgAl LDHexfoliationnanocompositewerechar acterizedbyX raydiffraction (XRD ) ,transmissionelectronmicroscopy (TEM ) ,andthermogravimetryanalysis (TGA ) .The…     

Synthesis of the first kinetically stable dibenzosilafulvene

The first stable dibenzosilafulvene, 9-{[8-(dimethylaminomethyl)-1-naphthyl]phenylsil-1-ylium}fluoren-9-ide (7a), was obtained in one step from 9-fluorenyllithium and chloro[8-(dimethylaminomethyl)-1-naphthyl]phenylsilane as a stable solvate with THF. The structure of the zwitterionic compound7a was established by¹H,¹³C, and²⁹Si NMR in solution and in the solid state. The reactions of compound7a with crotonaldehyde, ethanol, and triethylethylidenephosphorane are described. The data on the synthesis of alkoxy- and alkylthiochloro-9-fluorenylsilanes and their phosphonium salts are given. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 486–491, March, 1998.     

Preparation and thermal decomposition study of pyridinedicarboxylate intercalated layered double hydroxides

Supramolecular 2,3- and 2,5-pyridinedicarboxylate (PDC) intercalated ZnAl-layered double hydroxides (2,3- and 2,5-PDC–ZnAl–LDHs) have been prepared by ion exchange method. The structure and composition of the intercalated materials have been studied by X-ray diffraction (XRD) and inductively coupled plasma emission spectroscopy (ICP). The study indicates that the 2,3-PDC and 2,5-PDC anions are accommodated as interdigitated bilayer and monolayer arrangement respectively between the sheets of LDHs. Furthermore, their thermal decomposition processes were studied by the use of in situ high temperature X-ray diffraction (HT-XRD), and the combined technique of thermogravimetry-differential thermal analysis-mass spectrometry (TG-DTA-MS) under N2 atmosphere. Based on the comparison study on the temperatures of both decarboxylation and complete decomposition of interlayer PDC, it can be concluded that 2,5-PDC–ZnAl–LDHs has higher thermal stability than that of 2,3-PDC–ZnAl–LDHs.     

Chemical bond in alkali metal sulfates

In the context of the density functional theory of the local electron density the valence and differential density distribution in crystalline sulfates of M₂SO₄ (M is Li, Rb, and Cs) and double sulfates of MLiSO₄ were calculated using the pseudopotential method in the basis set of numerical atomic pseudo-orbitals. It is shown that in lithium sulfate crystallographically inequivalent oxygen atoms are in different charge states and have a different force of chemical bonding with sulfur. Anions are bonded to each other through lithium atoms that form tetrahedral complexes with oxygen. In rubidium sulfates the electron clouds of the anions overlap and chain structures form. Chemical bonding between the anion and the cation has an ionic nature. These features of the electron structure manifest themselves in double sulfates, where LiO₄ complexes that link the anionic chains also form, and heavy metals serve as cations.     

Two-dimensional double-quantum 2H NMR spectroscopy in the solid state under OMAS conditions: correlating 2H chemical shifts with quasistatic line shapes.

Solid-state 2H NMR spectroscopy is a well-established and versatile method to study molecular orientation and dynamics in selectively deuterated samples. Herein, we introduce a 2D 2H double-quantum (DQ) NMR experiment performed under fast magic-angle spinning with a slight offset of the magic angle (OMAS). The experiment combines 2H chemical-shift resolution with DQ-filtered quasistatic 2H line shapes. In this way, it is possible to separate 2H resonances and to independently determine 2H quadrupole couplings at multiple sites. While 2H chemical shifts are resolved in the 2H DQ dimension, the quadrupole parameters can be obtained from characteristic line shapes which are reintroduced in the second dimension by the magic-angle offset. The 2D 2H DQ OMAS experiment is demonstrated on L-histidine which was deuterated at multiple sites by recrystallisation from D2O.     

Effect of temperature on the solubility of carnallite type double salts

A method based on Pitzer's model has been used for calculation of the solubilities of carnallite type double salts crystallizing in the systems MeX–MgX₂–H₂O (Me=Li, NH₄, K, Rb, Cs; X=Cl, Br). The solubility of congruently soluble double salts was also determined experimentally at 25–75°C. The results from studies of the solubility diagrams of ternary carnallite type water-salt systems over a wide temperature range are summarized. It is found that the width of the crystallization region for each of the salts can be explained by the relative differences in the solubilities of the ternary solution components (MeX, MgX₂·6H₂O and MeX·MgX₂·6H₂O) and by a change of temperature, and by the effect of temperature on the solubility. A method is proposed for calculating Pitzer's ternary parameters of interionic interaction (_MN and _MNX) on the basis of experimental data for the solubility in water of the double salts crystallizing in the corresponding ternary water-salt systems.     

手性环丙烷类衍生物双水解转换的研究

具有四个新手性中心的螺环／环丙烷类化合物4在丙酮－12％HCl溶液中50℃下 发生双手性辅基－双水解转换反应，得到了手性环丙烷／双半缩醛类化合物，螺 [1-溴－4－羟基－5－氧杂－6－氧代双环[3.1.0]己烷－2，2′-(3′-亲核氧基－ 4′－羟基丁内酯）]（5），化学产率65％－79％，光学纯度ee≥98。通过元素分 析，[a]D^20,UV,IR,^1H NMR,^13C NMR,MS以及X射线四圆衍射测定，确认了它们的 化学结构、立体化学和绝对构型。该双半缩醛类化合物的合成方法学研究可为官能 团的转换，为某些复杂结构的手性化合物提供新的合成方法和途径。