02晶体生长结晶学与矿物学讲解

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百度百科 long range order,结晶学概念。指整体性的有序现象。 例如在一个单晶体的范围内,质点的有序分布延伸到整个晶格 的全部,亦即从整个晶体范围来看,质点的分布都是有序的。
教科书上(李胜荣,2012) 在晶体中若每种质点(黑点或圆圈)在整个图形中各自都呈现 规律的周期性重复。把周期重复的点用直线联结起来,可获 得平行四边形网格。可以想像,在三维空间,这种网格将构 成空间格子,这种在图形中贯彻始终的规律称为远程规律或 长程有序。
long-rBaidu Nhomakorabeange order
McGraw-Hill Dictionary of Scientific & Technical Terms
long-range order (solid-state physics) A tendency for some property of atoms in a lattice (such as spin orientation or type of atom) to follow a pattern which is repeated every few unit cells.
Encyclopæ dia Britannica
Atomic positions in a crystal exhibit a property called long-range order or translational periodicity; positions repeat in space in a regular array.
Wikipedia A quasiperiodic crystal, or, in short, quasicrystal, is a structure that is ordered but not periodic. A quasicrystalline pattern can continuously fill all available space, but it lacks translational
Wikipedia
The order can consist either in a full crystalline space group symmetry, or in a correlation. Depending on how the correlations decay with distance, one speaks of long-range order or short-range order.
symmetry(平移对称). While crystals, according to the
classical crystallographic restriction theorem, can possess only two, three, four, and six-fold rotational symmetries, the Bragg diffraction pattern of quasicrystals shows sharp peaks with other symmetry orders, for instance five-fold.
长程有序(long-range order) 即晶体内部的原子排列具有 延绵不断的有序性; 反之叫短程有序 (罗谷风,2010)
准晶体 Quasicrystal:
Encyclopæ dia Britannica
quasicrystal, also called quasi-periodic crystal, matter formed atomically in a manner somewhere between the amorphous solids of glasses (special forms of metals and other minerals, as well as common glass) and the precise pattern of crystals. Like crystals, quasicrystals contain an ordered structure, but the patterns are subtle and do not recur at precisely regular intervals.
准晶体 Quasicrystal:
McGraw-Hill Science & Technology Encyclopedia:
Quasicrystal:A solid with conventional crystalline
properties but exhibiting a point-group symmetry inconsistent with translational periodicity. Like crystals, quasicrystals display discrete diffraction patterns, crystallize into polyhedral forms, and have long-range orientational order, all of which indicate that their structure is not random. But the unusual symmetry and the finding that the discrete diffraction pattern does not fall on a reciprocal periodic lattice suggest a solid that is quasiperiodic. Their discovery in 1982 contradicted a long-held belief that all crystals would be periodic arrangements of atoms or molecules.
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