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News. 2024-05-17 Malvern Panalytical publishes a new release of their free, COD-derived search-match database. The new COD database file is meant to be used with all versions 4.x and 5.x of the PANalytical HighScore (Plus) software packages. It can be downloaded as one (7.1 GB) database file in .HSRDB format from the archive and is ready for use.
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A crystal is a solid where the atoms form a periodic arrangement. ( Quasicrystals are an exception, see below ). Not all solids are crystals. For example, when liquid water starts freezing, the phase change begins with small ice crystals that grow until they fuse, forming a polycrystalline structure.
Crystal - Structure, Lattice, Symmetry: Crystals can be grown under moderate conditions from all 92 naturally occurring elements except helium, and helium can be crystallized at low temperatures by using 25 atmospheres of pressure. Binary crystals are composed of two elements. There are thousands of binary crystals; some examples are sodium chloride (NaCl), alumina (Al2O3), and ice (H2O ...
2024年4月12日 · Crystal, any solid material in which the component atoms are arranged in a definite pattern and whose surface regularity reflects its internal symmetry. Crystals are classified in general categories, such as insulators, metals, semiconductors, and molecular solids.
2022年11月16日 · Because the crystal structure is the infinite arrangement of its structural units (cells) in space, the crystal microstructure must have symmetry elements that cannot appear in the macroscopic symmetry, and it is also called nonpoint symmetry operation. Nonpoint symmetry operation includes the following. (1) Screw axis.
All crystal lattices are built of repeating unit cells. In a unit cell, an atom's coordination number is the number of atoms it is touching. The simple cubic has a sphere at each corner of a cube. Each sphere has a coordination number of 6 and there is 1 atom per unit cell. The body-centered cubic (bcc) has a sphere at each corner of a cube and ...
