Curie group
The Curie groups or continuous point groups are all those point groups that have at least one continuous rotational symmetry . They are named after Pierre Curie , who used them to describe the symmetry of electric and magnetic fields. There are seven Curie groups divided into two systems.
The seven Curie groups
The cylindrical system
The cylinders or cones given as examples are finite bodies. They are rotated or twisted in such a way that the axes of these bodies remain unchanged in any case.
Hermann Mauguin symbol | Hermann Mauguin short symbol | Schoenflies icon | possible physical properties | example |
---|---|---|---|---|
optically active, enantiomorphic, piezoelectric, pyroelectrically polar | rotating cone | |||
rotating cylinder | ||||
optically active, enantiomorphic, piezoelectric | Cylinder that is exposed to torsional forces of opposite magnitude | |||
piezoelectric, pyroelectric | standing cone | |||
standing cylinder |
|
The spherical system
Hermann Mauguin symbol | Hermann Mauguin short symbol | Schönflies symbol | possible physical properties | example |
---|---|---|---|---|
optically active, enantiomorphic | sphere filled with an optically active liquid | |||
sphere filled with an isotropic liquid |
Applications
The Curie groups are used to describe the symmetry of fields. This is required when applying the Curie principle to determine the properties of a body in a field.
literature
- Will Kleber , Hans-Joachim Bautsch , Joachim Bohm : Introduction to crystallography. 19th, improved edition. Edited by Joachim Bohm and Detlef Klimm. Oldenbourg Wissenschaftsverlag, Munich 2010, ISBN 978-3-486-59075-3 .
Web links
Individual evidence
- ↑ Pierre Curie: Sur la symétrie dans les phénomènes physiques, symétrie d'un champ électrique et d'un champ magnétique. In: Journal de Physique théorique et appliquée. Ser. 3, Vol. 3, No. 1, 1894, pp. 393-415, doi : 10.1051 / jphystap: 018940030039300 .