Coordination Number definition of Coordination Number in the Free Online Encyclopedia.

coordination number [kō‚ȯrd·ən′ā·shən ‚nəm·bər]

(physics)

The number of nearest neighbors of a point in a space lattice, of an atom or an ion in a solid, or of an anion or cation in a solution.

Coordination Number

in crystallography, the number of identical neighboring atoms or ions closest to a given atom or ion in a crystal. Straight lines connecting the centers of nearest atoms or ions in a crystal form the coordination polyhedron, with the given atom in its center.

Different polyhedrons may correspond to the same coordination number. The coordination number in the structures of diamond, silicon, germanium, and sphalerite is 4, and the coordination polyhedron is a tetrahedron. Each sodium ion in sodium chloride, NaCl, is surrounded by six chlorine ions, and each chlorine ion is surrounded by six sodium ions, meaning that the coordination numbers are 6 for both types of ions and the corresponding polyhedron is an octahedron. The coordination number of calcium ions in fluorite, CaF₂, is 8 and the corresponding polyhedron is a cube, whereas the coordination number for F ions is 4 and the coordination polyhedron is a tetrahedron. The highest possible coordination number is 12, which is typical of metals with cubic or hexagonal close-packed structure. Metals with a body-centered lattice have a coordination number of 8. Semiconductor crystals, which do not have close packing of atoms, have coordination numbers of 4 or 6.

In chemistry, the coordination number is the number of atoms or atomic groups directly bonded to a given atom in complex compounds. The concept of coordination numbers is also used in descriptions of fluids and amorphous bodies. In this case, the coordination number is the average number of the nearest neighbors of the atom; it may be fractional. The coordination number is a measure of short-range order in liquids and amorphous bodies.

M. P. SHASKOL’SKAIA

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No references found	The coordination numbers of rare-earth ions are generally 7-9 and the coordinated groups of VBA a polymer chain unit only provide two coordinated oxygen atoms for the limited hindrance and so there should be two other carboxyl groups of VBA polymer unit coordinating to [Eu. Facile fabrication of novel Eu-containing copolymer and luminescent ... by Huang, Ziqun; Zhang, Huaihong; Guo, Jiaxiu; Wang, Jianli; Chen, Yaoqiang / Polymer Engineering and Science of Stuttgart) introduces clusters, nanoparticles and Feynman's vision, then describes bulk and interface, geometric structure, magic numbers, coordination numbers of small clusters, electronic structure, magnetic properties, thermodynamics for finite size systems, absorption, phase behavior, the dynamics of surface layers and in pores, nucleation and phase transitions within the dynamics of clusters, phase transitions of two-dimensional systems, and catalysis by metallic particles. Nanoscopic materials; size-dependent phenomena by SciTech Book News And the coordination number of Na-SAP would reach to six or more [20]. Synthesis of poly(sodium acrylate-co-sodium 1-(acryloyloxy) ... by Chen, Zhenbin; Liu, Mingzhu; Qi, Xiaohua; Liu, Zhen / Polymer Engineering and Science	coordinate data transmitter coordinate indexing Coordinate Measuring Device coordinate plotter coordinate storage coordinate system coordinate systems coordinate transformation coordinate valence Coordinate-Measuring Machine coordinated complex coordinated geometry coordinated transpositions Coordinated Universal Time coordinated-axis control Coordinates Coordinating Committee for Intercontinental Research Networks Coordinating Computation Center coordinating holes Coordination coordination chemistry coordination complex Coordination Compound coordination language coordination lattice Coordination Number coordination polygon coordination polyhedron coordination polymer Coordinatograph coordinator Coorg Coornhert, Dirck Volckertszoon Coornhert, Dirk Volkertszoon coorongite Coors, Adolph Coos Coos Bay Coos County Coosa Coosa County Coosa River Coot Coover, Robert Cop Copacabana Copaiba copaiba balsam Copal copal varnish Copalis National Wildlife Refuge	Coordination Group for Meteorological Satellites Coordination Group Publications Ltd Coordination Handicap et Autonomie Coordination Handicap Locale Coordination Handicap Normandie Coordination Humaniste des Professionnels de Santé Coordination in Parallel and Distributed Applications and Activities coordination language Coordination Language Facility coordination lattice Coordination Lesbienne en France Coordination Level Coordination Life Interchangeability, Function & Safety Coordination Line Coordination Mammalogique du Nord de la France Coordination Médicale Hospitalière Coordination Models and Languages Coordination Nationale d'Action pour la Paix et la Démocratie Coordination Nationale des Collectifs des Assistants de Service Social Coordination Nationale des Étudiants en Soins Infirmiers Coordination Nationale des Opérateurs en Alphabétisation du Senegal Coordination Nationale des Organisations Paysannes Coordination Nationale Étudiante Coordination Nationale Infirmière Coordination Number coordination numbers coordination numbers Coordination of Action Research on AIDS and Migration Coordination of Action Research on AIDS and Mobility Coordination of Action Research on AIDS and Mobility Asia Coordination of Afghan Relief Coordination of Animal Rescue Agencies Coordination of Atomic Operations Coordination of Atomic Operations Standing Operating Procedures Coordination Of Benefits Coordination of Benefits Agreement coordination of benefits clause coordination of benefits clause coordination of benefits clause coordination of benefits clause Coordination of Benefits Contractor Coordination of Distributed Activities Coordination of Domain-Specific Languages Coordination of European NGOs Networking on Trade Coordination of European Picture Agencies Press Stock Heritage Coordination of Humanitarian Assistance Coordination of IST Coordination of Runaway Youth coordination of services coordination of services coordination of services coordination of services Coordination of Space Techniques for Geodesy and Geodynamics Coordination of University Research for Synergy and Effectiveness Coordination on Geostationary Meteorological Satellites

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The coordination numbers of rare-earth ions are generally 7-9 and the coordinated groups of VBA a polymer chain unit only provide two coordinated oxygen atoms for the limited hindrance and so there should be two other carboxyl groups of VBA polymer unit coordinating to [Eu.

Facile fabrication of novel Eu-containing copolymer and luminescent ... by Huang, Ziqun; Zhang, Huaihong; Guo, Jiaxiu; Wang, Jianli; Chen, Yaoqiang / Polymer Engineering and Science

of Stuttgart) introduces clusters, nanoparticles and Feynman's vision, then describes bulk and interface, geometric structure, magic numbers, coordination numbers of small clusters, electronic structure, magnetic properties, thermodynamics for finite size systems, absorption, phase behavior, the dynamics of surface layers and in pores, nucleation and phase transitions within the dynamics of clusters, phase transitions of two-dimensional systems, and catalysis by metallic particles.

Nanoscopic materials; size-dependent phenomena by SciTech Book News

And the coordination number of Na-SAP would reach to six or more [20].

Synthesis of poly(sodium acrylate-co-sodium 1-(acryloyloxy) ... by Chen, Zhenbin; Liu, Mingzhu; Qi, Xiaohua; Liu, Zhen / Polymer Engineering and Science

coordinate data transmitter

coordinate indexing

Coordinate Measuring Device

coordinate transformation

coordinate valence