Coordination geometries and crystal structures of cadmium(II) complexes with a new amino alcohol (NN′O) ligand

2012 ◽  
Vol 65 (13) ◽  
pp. 2221-2233 ◽  
Author(s):  
Mohammad Hakimi ◽  
Zahra Mardani ◽  
Keyvan Moeini ◽  
Manuel A. Fernandes
Keyword(s):  
Crystal Structures ◽  
Amino Alcohol

scholarly journals Crystal structures of chiral 2-[bis(2-chloroethyl)amino]-1,3,2-oxazaphospholidin-2-one derivatives for the absolute configuration at phosphorus

2018 ◽  
Vol 74 (9) ◽  
pp. 1330-1335
Author(s):  
Laurence N. Rohde Jr ◽  
Matthias Zeller ◽  
John A. Jackson
Keyword(s):  
Chemical Shift ◽  
Crystal Structures ◽  
Absolute Configuration ◽  
Amino Alcohol ◽  
Nitrogen Mustard ◽  
Spatial Relationship ◽  
Nmr Chemical Shift ◽  
Enantiomerically Pure ◽  
Flash Column Chromatography ◽  
Relationship Of

`Nitrogen mustard' bis(2-chloroethyl)amine derivatives (2R,4S,5R)- and (2S,4S,5R)-2-[bis(2-chloroethyl)amino]-3,4-dimethyl-5-phenyl-1,3,2-oxazaphospholidin-2-one (2a and 2b, respectively), C14H21Cl2N2O2P, and (2R,4R)- and (2S,4R)-2-[bis(2-chloroethyl)amino]-4-isobutyl-1,3,2-oxazaphospholidin-2-one (3a and 3b, respectively), C10H21Cl2N2O2P, were synthesized as a mixture of diastereomers through a 1:1 reaction of enantiomerically pure chiral amino alcohols with bis(2-chloroethyl)phosphoramidic dichloride. Flash column chromatography yielded diastereomerically pure products, as supported by 31P NMR. The crystal structures of 2b and 3b were obtained to determine their absolute configuration at phosphorus, and 31P NMR chemical shift trends are proposed based on the spatial relationship of the bis(2-chloroethyl)amine moiety and the chiral substituent of the amino alcohol. Oxazaphospholidinones were observed to have a more downfield 31P NMR chemical shift when the aforementioned substituents are in a syn configuration and vice versa for when they are anti.

Pollutant Identification by Selected Area Electron Diffraction

1974 ◽  
Vol 32 ◽  
pp. 532-533
Author(s):  
R. E. Ferrell ◽  
G. G. Paulson ◽  
C. W. Walker
Keyword(s):  
Thermal Treatment ◽  
Electron Diffraction ◽  
Sample Preparation ◽  
Crystal Structures ◽  
Water Samples ◽  
Environmental Samples ◽  
Short Review ◽  
Selected Area Electron Diffraction ◽  
Multiple Component

Selected area electron diffraction (SAD) has been used successfully to determine crystal structures, identify traces of minerals in rocks, and characterize the phases formed during thermal treatment of micron-sized particles. There is an increased interest in the method because it has the potential capability of identifying micron-sized pollutants in air and water samples. This paper is a short review of the theory behind SAD and a discussion of the sample preparation employed for the analysis of multiple component environmental samples.

The Imaging of Crystal Structures and Crystal Defects

1978 ◽  
Vol 36 (3) ◽  
pp. 207-217
Author(s):  
J.M. Cowley
Keyword(s):  
Electron Microscope ◽  
Crystal Structures ◽  
Phase Contrast ◽  
Crystal Defects ◽  
Atom Density ◽  
Lack Of Information ◽  
Spatial Frequencies

The problem of "understandinq" electron microscope imaqes becomes more acute as the resolution is improved. The naive interpretation of an imaqe as representinq the projection of an atom density becomes less and less appropriate. We are increasinqly forced to face the complexities of coherent imaqinq of what are essentially phase objects. Most electron microscopists are now aware that, for very thin weakly scatterinq objects such as thin unstained bioloqical specimens, hiqh resolution imaqes are best obtained near the optimum defocus, as prescribed by Scherzer, where the phase contrast imaqe qives a qood representation of the projected potential, apart from a lack of information on the lower spatial frequencies. But phase contrast imaqinq is never simple except in idealized limitinq cases.

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.

Advancing the use of Voronoi–Dirichlet polyhedra to describe interactions in organic molecular crystal structures by the example of galunisertib polymorphs

CrystEngComm ◽  
2021 ◽  
Author(s):  
Viktor N. Serezhkin ◽  
Anton V. Savchenkov
Keyword(s):  
Crystal Structures ◽  
Molecular Crystal ◽  
Noncovalent Interactions ◽  
Organic Molecular Crystal ◽  
Universal Approach ◽  
Structure Properties

The universal approach for studying structure/properties relationships shows that every polymorph of galunisertib is characterized with unique noncovalent interactions.

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