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167:. Tridentate ligands usually bind via two kinds of connectivity, called "mer" and "fac." "fac" stands for facial, the donor atoms are arranged on a triangle around one face of the octahedron. "mer" stands for meridian, where the donor atoms are stretched out around one half of the octahedron. Cyclic tridentate ligands such as
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Relationship between "linear" bi-, tri- and tetradentate ligands (red) bound to an octahedral metal center. The structures marked with * are chiral owing to the backbone of the tetradentate ligand.
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and classified by their denticity. Some atoms cannot form the maximum possible number of bonds a ligand could make. In that case one or more
228:(DTPA) are octadentate. They are particularly useful for binding lanthanide ions, which typically have coordination numbers greater than 6.
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In general, the stability of a metal complex correlates with the denticity of the ligands, which can be attributed to the
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because hapticity refers exclusively to ligands where the coordinating atoms are contiguous. In these cases the
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are a quantitative measure to assess the thermodynamic stability of coordination complexes.
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Zelewsky, A. "Stereochemistry of Coordination Compounds" John Wiley: Chichester, 1995.
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Number of atoms in a ligand that bond to the central atom of a coordination complex
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Bidentate (also called didentate) ligands bind with two atoms, an example being
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471:, 2nd ed. (the "Gold Book") (1997). Online corrected version: (2006–) "
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349:, 2nd ed. (the "Gold Book") (1997). Online corrected version: (2006–) "
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of the ligand are unused. Such sites can be used to form a bond with another
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describes an EDTA ligand that coordinates through 6 non-contiguous atoms.
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bind with five atoms, an example being ethylenediaminetriacetic acid.
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Ligands of denticity greater than 6 are well known. The ligands
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84:. The denticity of a ligand is described with the Greek letter
76:). Ligands with more than one bonded atom are called
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1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetate
193:ligands are tetradentative, an example being the
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217:(although it can bind in a tetradentate manner).
181:bind with four donor atoms, an example being
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383:η (eta or hapto) in inorganic nomenclature
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56: 'tooth') refers to the number of
213:bind with six atoms, an example being
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468:Compendium of Chemical Terminology
436:Compendium of Chemical Terminology
407:Compendium of Chemical Terminology
378:Compendium of Chemical Terminology
346:Compendium of Chemical Terminology
300:Compendium of Chemical Terminology
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277:2.4MB PDF - Slide 3 on denticity
226:diethylene triamine pentaacetate
149:Structure of the pharmaceutical
275:EDTA chelation lecture notes.
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95:Denticity is different from
103:('eta') notation is used.
88:('kappa'). For example, κ-
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443:in inorganic nomenclature
353:in inorganic nomenclature
175:bind in a facial manner.
119:Polydentate ligands are
481:10.1351/goldbook.C01012
452:10.1351/goldbook.M03659
420:10.1351/goldbook.B00741
391:10.1351/goldbook.H01881
362:10.1351/goldbook.K03366
313:10.1351/goldbook.D01594
187:tris(2-aminoethyl)amine
499:Coordination chemistry
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42:coordination chemistry
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205:Pentadentate ligands
183:triethylenetetramine
179:Tetradentate ligands
66:coordination complex
251:Stability constants
241:Stability constants
211:Hexadentate ligands
36:monodentate ligands
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161:Tridentate ligands
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72:(sometimes called
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18:Multidentate
224:(DOTA) and
191:macrocyclic
165:terpyridine
151:Oxaliplatin
78:polydentate
70:monodentate
493:Categories
351:κ (kappa)
329:047195599X
282:References
74:unidentate
48:(from
473:chelation
305:denticity
195:porphyrin
97:hapticity
46:denticity
34:Atom with
441:µ- (mu)
257:See also
173:9-ane-S3
107:use the
263:Chelate
115:Classes
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62:ligand
54:dentis
463:IUPAC
431:IUPAC
402:IUPAC
373:IUPAC
341:IUPAC
295:IUPAC
58:donor
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50:Latin
325:ISBN
215:EDTA
199:heme
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169:TACN
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109:μ
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