Gas-phase electron diffraction, structure

IR and Raman spectroscopy have been commonly used and, for example, the effects of pressure on the Raman spectrum of a zinc compound with a N2C12 coordination sphere around the metal, have been investigated.28 IR spectroscopy has been utilized in studies of the hydration of zinc in aqueous solution and in the hydrated perchlorate salt.29 Gas phase chemistry of zinc complexes has been studied with some gas phase electron diffraction structures including amide and dithiocarbamate compounds.30-32... 

This SF6-acetylene can also be obtained in —50% yield by dehydrobro-mination of SF5CH=CHBr (135). The gas-phase electron diffraction structure of SF5C=CH is reported (136). In the H NMR spectrum, the acetylenic proton resonates at a more shielded position and appears as a pentet with JF H = 3 Hz (134). This suggests that it couples significantly only with the four equatorial S-F atoms and not the axial S-F atom. Of particular interest are comparative 19F NMR spectral studies of F5SC=CH and other saturated hydrocarbons/fluorocarbons containing the SF5 group (137). 

Tetrachloride and tetrabromide complexes are known for thorium, protactinium, uranium, neptunium, and plutonium. These are similarly produced by halide-based oxidation of metals or hydrides, or by halogenation of oxides. A common structural type is reported for most compounds. The reported structure of thorium tetrachloride reveals that the coordination geometry about the metal is dodecahedral.The compounds are generally volatile and can be sublimed. The gas-phase electron diffraction structure of suggests that the molecule is... 

Structural data of a diaziridine come from gas phase electron diffraction measurements (74CC397). The N—N bond of 3-methyldiaziridine (24) is longer than in hydrazine (1.449 A) the C—N bond distances in (24) and in diazirine are nearly equal (1.479 versus 1.482 A),... 

Schei, S. H., A. Almenningen, and J. Almlof. 1984b. 1,2,4,5-Tetrafluorobenzene Molecular Structure as Determined by Gas-Phase Electron Diffraction and by Ab Initio Calculations. J. Mol. Struct. 112, 301-308. 

A gas-phase electron diffraction study95 has shown that cis -hexatriene has a slightly twisted structure (torsional angle of 10° around the central C=C bond) and the lengths of the terminal C=C, central C=C and C—C bonds are 1.336, 1.362 and... 

GAS-PHASE ELECTRON DIFFRACTION FOR MOLECULAR STRUCTURE DETERMINATION... 

Abstract Gas-phase electron diffraction is a unique source of structural information on... 

The present chapter provides an overview of the technique and its application, its purpose is to give an impression for the newcomer, but is not meant to be a guide for work with the technique. A two-volume monograph by experts is available for advanced study of gas-phase electron diffraction and its stereochemical applications. Gas-phase electron diffiaction has also been described in the context of other techniques of structure determination with emphases of producing accurate structural information. 

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