Difference between revisions of "Absolute structure"
From Online Dictionary of Crystallography
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| − | Both the ''absolute structure'' of a crystal and the ''absolute configuration'' of a molecule describe the spatial arrangement of atoms in their respective object. However the object, its symmetry and the method of its specification are different. The table | + | Both the ''absolute structure'' of a crystal and the ''absolute configuration'' of a molecule describe the spatial arrangement of atoms in their respective object. However the object, its symmetry and the method of its specification are different. The table compares the two cases. |
Absolute Structure Absolute Configuration | Absolute Structure Absolute Configuration | ||
Revision as of 11:05, 15 February 2006
Definition
The spatial arrangement of the atoms of a physically identified non-centrosymmetric crystal and its description by way of unit-cell dimensions, space group, and representative coordinates of all atoms.
Background
Both the absolute structure of a crystal and the absolute configuration of a molecule describe the spatial arrangement of atoms in their respective object. However the object, its symmetry and the method of its specification are different. The table compares the two cases.
Absolute Structure Absolute Configuration
Property spatial arrangement spatial arrangement
Content atoms atoms
Object crystal molecule
Symmetry non-centrosymmetric chiral
Specification crystallographic stereochemical
space group CIP
cell dimensions
atomic coordinates
Related chemical terms
The IUPAC Basic Terminology of Stereochemistry contains definitions of related chemical terms of use to the crystallographer, viz: absolute configuration, chiral, chirality, chirality sense, enantiomer, enantiomerically pure, enantiomorph, racemate, racemic, racemic conglomerate and relative configuration.