coordination

A coordination entity is composed of a central atom, usually that of a metal, to which is attached a surrounding array of other atoms or group of atoms, each of which is called a ligand. A coordination entity may be a neutral molecule, a cation or an anion. The ligands may be viewed as neutral or ionic entities that are bonded to an appropriately charged central atom. It is standard practice to think of the ligand atoms that are directly attached to the central atom as defining a coordination polyhedron (tetrahedron, square plane, octahedron, etc.) about the central atom. The coordination number is defined as being equal to the number of sigma-bonds between ligands and the central atom; this definition is not necessarily appropriate in all areas of (coordination) chemistry. In a coordination formula, the central atom is listed first. The formally anionic ligands appear next and they are listed in alphabetic order according to the first symbols of their formula. The neutral ligands follow, also in alphabetical order, according to the same principle. The formula for the entire coordination entity, whether charged or not, is enclosed in square brackets. In a coordination name, the ligands are listed in alphabetical order, without regard to charge, before the name of the central atom. Numerical prefixes indicating the number of ligands are not considered in determining that order. All anionic coordination entities take the ending -ate, whereas no distinguishing termination is used for cationic or neutral coordination entities.



The term "coordination" was found in the following pages:

ICBIC16: 16th International Conference on BioInorganic Chemistry | EVISA's Agenda of Events
Journals database: Applied Organometallic Chemistry
Journals database: Zeitschrift für Naturforschung, Teil B:
1st European Chemistry Congress | EVISA's Agenda of Events
Methylmercury: What have we learned from Minamata Bay? | EVISA's News
AsBIC8: 8th Asian Biological Inorganic Chemistry Conference | EVISA's Agenda of Events
Link database: XAFS Spectroscopy as a Speciation Tool
Journals database: Doklady Chemistry
Journals database: Polyhedron
Instrument database: Dionex Corporation - Summit HPLC Analytical System
Link database: Australia: University of Western Sydney: Biologically Active Drugs by Design Group
Company database: Geological Survey of Japan, AIST
Company database: The International Association of Forensic Toxicologists (TIAFT)
Material database: United States Pharmacopeial Convention (USP) - Chromium picolinate
ICCST-11: 11th International Conference on the Chemistry of Selenium and Tellurium | EVISA's Agenda of Events
First strontium isotope map of Sub-Saharan Africa is a powerful tool for tracing origins in archaeology and wildlife trafficking | EVISA's News
Company database: Science Council of Japan
EuroBic 10: 10th European Biological Inorganic Chemistry Conference | EVISA's Agenda of Events
Tracking down the source of human exposure to mercury by analysing human hair | EVISA's News
EuroBIC-16: 16th European Biological Inorganic Chemistry Conference | EVISA's Agenda of Events