Crystallographic point group — In crystallography, a crystallographic point group is a set of symmetry operations, like rotations or reflections, that leave a central point fixed while moving other directions and faces of the crystal to the positions of features of the same… … Wikipedia
Point groups in three dimensions — In geometry, a point group in three dimensions is an isometry group in three dimensions that leaves the origin fixed, or correspondingly, an isometry group of a sphere. It is a subgroup of the orthogonal group O(3), the group of all isometries… … Wikipedia
Crystallographic restriction theorem — The crystallographic restriction theorem in its basic form was based on the observation that the rotational symmetries of a crystal are usually limited to 2 fold, 3 fold, 4 fold, and 6 fold. However, quasicrystals can occur with other symmetries … Wikipedia
Point group — The Bauhinia blakeana flower on the Hong Kong flag has C5 symmetry; the star on each petal has D5 symmetry. In geometry, a point group is a group of geometric symmetries (isometries) that keep at least one point fixed. Point groups can exist in a … Wikipedia
crystallographic knot — kristalografinis mazgas statusas T sritis chemija apibrėžtis Medžiagos dalelės (atomo, jono, molekulės) vieta kristalo erdvinėje gardelėje. atitikmenys: angl. crystallographic knot; crystallographic point rus. кристаллографическая точка;… … Chemijos terminų aiškinamasis žodynas
Crystallographic image processing — (CIP) is a set of methods for determining the atomic structure of crystalline matter from high resolution electron microscopy (HREM) images obtained in a transmission electron microscope (TEM). The term was created in the research group of Sven… … Wikipedia
Crystallographic database — A crystallographic database is a database specifically designed to store information about crystals and crystal structures. Crystals are solids having, in all three dimensions of space, a regularly repeating arrangement of atoms, ions, or… … Wikipedia
Crystallographic defect — Crystalline solids exhibit a periodic crystal structure. The positions of atoms or molecules occur on repeating fixed distances, determined by the unit cell parameters. However, the arrangement of atom or molecules in most crystalline materials… … Wikipedia
Point groups in two dimensions — In geometry, a point group in two dimensions is an isometry group in two dimensions that leaves the origin fixed, or correspondingly, an isometry group of a circle. It is a subgroup of the orthogonal group O(2), the group of all isometries which… … Wikipedia
Crystallographic defects in diamond — Synthetic diamonds of various colors grown by the high pressure high temperature technique, the diamond size is 2 mm … Wikipedia