Intermolecular [2 + 2 + 2] cycloaddition reactions of alkynes and alkenes mediated by cobalt: x-ray crystal structures of two isomeric (.eta.5-cyclopentadienyl)(.eta.4-1,3-cyclohexadiene)cobalt complexes

1988 ◽  
Vol 7 (6) ◽  
pp. 1241-1253 ◽  
Author(s):  
David W. Macomber ◽  
Akhilkumar G. Verma ◽  
Robin D. Rogers
Keyword(s):  
Crystal Structures ◽  
Cobalt Complexes ◽  
Cycloaddition Reactions ◽  
X Ray

Cobalt complexes with pnicogen (phosphine or pyridine) and thiolato ligands. Syntheses, x-ray crystal structures and spectroscopic characterization

Polyhedron ◽  
1993 ◽  
Vol 12 (8) ◽  
pp. 871-878 ◽  
Author(s):  
Bei-Sheng Kang ◽  
Yong-Jin Xu ◽  
Jing-Hai Peng ◽  
Da-Xu Wu ◽  
Xue-Tai Chen ◽  
...  
Keyword(s):  
Crystal Structures ◽  
Cobalt Complexes ◽  
Spectroscopic Characterization ◽  
X Ray

Transmission electron microscope studies in special ceramics

1978 ◽  
Vol 36 (1) ◽  
pp. 268-269
Author(s):  
A. Zangvil ◽  
L.J. Gauckler ◽  
G. Schneider ◽  
M. Rühle
Keyword(s):  
Phase Diagrams ◽  
Crystal Structures ◽  
Thin Foil ◽  
Limited Extent ◽  
Complex Materials ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Electron Microscopes ◽  
Lattice Resolution

The use of high temperature special ceramics which are usually complex materials based on oxides, nitrides, carbides and borides of silicon and aluminum, is critically dependent on their thermomechanical and other physical properties. The investigations of the phase diagrams, crystal structures and microstructural features are essential for better understanding of the macro-properties. Phase diagrams and crystal structures have been studied mainly by X-ray diffraction (XRD). Transmission electron microscopy (TEM) has contributed to this field to a very limited extent; it has been used more extensively in the study of microstructure, phase transformations and lattice defects. Often only TEM can give solutions to numerous problems in the above fields, since the various phases exist in extremely fine grains and subgrain structures; single crystals of appreciable size are often not available. Examples with some of our experimental results from two multicomponent systems are presented here. The standard ion thinning technique was used for the preparation of thin foil samples, which were then investigated with JEOL 200A and Siemens ELMISKOP 102 (for the lattice resolution work) electron microscopes.

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