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Baris 2: Dalam [[mineralogi]] dan [[kristalografi]], '''struktur kristal''' adalah suatu susunan khas atom-atom dalam suatu [[kristal]]. Suatu struktur kristal dibangun oleh '''sel unit''', sekumpulan [[atom]] yang tersusun secara khusus, yang secara periodik berulang dalam tiga dimensi dalam suatu [[kisi Bravais\|kisi]]. Spasi antar sel unit dalam segala arah disebut ''parameter kisi''. Sifat [[simetri]] kristalnya terwadahi dalam [[gugus spasi]]nya. Struktur dan simetri suatu emmainkan peran penting dalam menentukan sifat-sifatnya, seperti sifat [[pembelahan (kristal)\|pembelahan]], [[struktur pita]] listrik, dan [[optik kristal\|optiknya]]. <!--▼ ==Sel unit== ASatu sel unit ~~cell~~adalah ~~is a~~susunan spatial ~~arrangement of [[~~atom~~\|atoms]]~~-atom ~~which~~yang ismengekor ~~[[tiling\|tiled]]~~secara intiga ~~three-dimensional~~dimensi ~~space~~untuk tomenggambarkan ~~describe the crystal~~kristalnya. ~~The~~Posisi ~~positions~~atom ofdalam ~~the~~sel ~~atoms~~unit ~~inside~~digambarkan ~~the~~sebagai unit ~~cell~~asimetri ~~are described by the asymmetric unit or~~atau '''basis''', ~~the~~sekumpulan ~~set~~posisi ~~of atomic positions~~atom <math>(x_i, y_i, z_i)</math> ~~measured~~yang diukur ~~from~~dari asuatu ~~lattice~~titik ~~point~~kisi. Setiap struktur kristal memiliki ''sel unit konvensional'' yang biasanya dipilih agar kisi yang dihasilkan sesimetris mungkin. Meski begitu, sel unit konvensional tidak selalu pilihan terkecil yang mungkin. Suatu '''sel unit primitif''' dari suatu struktur kristal merupakan sel unit terkecil yang mungkin yang dapat dibangun, sehingga, ketika disusun, akan mengisi spasi/ruang secara sempurna. [[Sel Wigner-Seitz]] adalah suatu sel primitif khas yang memiliki simetri yang sama dengan kisinya. For each crystal structure there is a ''conventional unit cell'', usually chosen to make the resulting lattice as symmetric as possible. However, the conventional unit cell is not always the smallest possible choice. A '''primitive unit cell''' of a particular crystal structure is the smallest possible unit cell one can construct such that, when tiled, it completely fills space. A [[Wigner-Seitz cell]] is a particular kind of primitive cell which has the same symmetry as the lattice. ~~==Crystal system==~~ The '''crystal system''' is the [[point group]] of the lattice (the set of rotation and reflection symmetries which leave a lattice point fixed), not including the positions of the atoms in the unit cell. There are seven unique crystal systems. The simplest and most symmetric, the [[cubic (crystal system)\|cubic]] (or isometric) system, has the symmetry of a [[Cube (geometry)\|cube]]. The other six systems, in order of decreasing symmetry, are [[Hexagonal (crystal system)\|hexagonal]], [[tetragonal]], [[rhombohedral]] (also known as trigonal), [[orthorhombic]], [[monoclinic]] and [[triclinic]]. Some crystallographers consider the hexagonal crystal system not to be its own crystal system, but instead a part of the trigonal crystal system.▼ ~~==Classification of lattices ==~~ ==Sistem kristal== ▲~~The~~ <!--'''~~crystal~~Sistem ~~system~~kristal''' is the [[point group]] of the lattice (the set of rotation and reflection symmetries which leave a lattice point fixed), not including the positions of the atoms in the unit cell. There are seven unique crystal systems. The simplest and most symmetric, the [[cubic (crystal system)\|cubic]] (or isometric) system, has the symmetry of a [[Cube (geometry)\|cube]]. The other six systems, in order of decreasing symmetry, are [[Hexagonal (crystal system)\|hexagonal]], [[tetragonal]], [[rhombohedral]] (also known as trigonal), [[orthorhombic]], [[monoclinic]] and [[triclinic]]. Some crystallographers consider the hexagonal crystal system not to be its own crystal system, but instead a part of the trigonal crystal system. -->▼ ==Klasifikasi kisi== ▲<!-- {\| align=right border=1 style=margin-left:1em \|'''Crystal system''' Baris 76 ⟶ 75: ==Defects in crystals== Real crystals feature [[crystallographic defect\|defects]] or irregularities in the ideal arrangements described above and it is these defects that critically determine many of the electrical and mechanical properties of real materials. In particular [[dislocation]]s in the crystal lattice allow [[shear]] at much lower stress than that needed for a perfect crystal structure. --> == ~~See~~Lihat ~~also~~pula ==▼ [[~~Crystal~~Kristal]]▼ [[Kristalografi]] [[Kerusakan kristalografis]] [[Pertumbuhan kristal]] [[Kristal cair]] [[Pembelahan (kristal)]] Untuk embaran lebih rinci mengenai penerapan teknologi yang spesifik, lihat [[rekayasa bahan]], [[ilmu bahan]], [[keramik]], [[metalurgi]], atau [[fisika bahan]]. ▲== See also == ▲[[Crystal]] [[Crystallography]] [[Crystallographic defect]] [[Crystal growth]] [[Liquid crystal]] [[Cleavage (crystal)]] ~~For more detailed information in specific technology applications see [[materials engineering]], [[materials science]], [[ceramics]], [[metallurgy]], or [[materials physics]].~~ ▲--> ==Pranala keluar== *[http://www.planewave.de/icp/atoms/atoms.sgml-7.html Appendix A from the manual for Atoms, software for XAFS]

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