Metal–ligand multiple bond

<p>In <a href="/facts/Organometallic_chemistry/bhqFz2P0">organometallic chemistry</a>, a metal–ligand multiple bond describes the interaction of certain <a href="/facts/Ligand/6etB3qeW">ligands</a> with a <a href="/facts/Metal/PT8hNX6R">metal</a> with a <a href="/facts/Bond_order/Tdb1zgTc">bond order</a> greater than one. <a href="/facts/Coordination_complex/1tCyeQUm">Coordination complexes</a> featuring multiply bonded ligands are of both scholarly and practical interest. <a href="/facts/Transition_metal_carbene_complex/LPIFUdjL">transition metal carbene complexes</a> catalyze the <a href="/facts/Olefin_metathesis/6G4u1ray">olefin metathesis</a> reaction. Metal oxo intermediates are pervasive in oxidation catalysis.
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<p>As a cautionary note, the classification of a metal–ligand bond as being "multiple" bond order is ambiguous and even arbitrary because <a href="/facts/Bond_order/Tdb1zgTc">bond order</a> is a formalism. Furthermore, the usage of multiple bonding is not uniform. Symmetry arguments suggest that most ligands engage metals via multiple bonds. The term 'metal–ligand multiple bond" is often reserved for ligands of the type CRn and NRn (n = 0, 1, 2) and ORn (n = 0, 1) where R is H or an organic substituent, or <a href="/facts/Pseudohalide/9DMN43ya">pseudohalide</a>. Historically, CO and NO+ are not included in this classification, nor are <a href="/facts/Halide/ujYu8kGD">halides</a>.
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Metal–ligand multiple bond open-in-new

Metal–ligand multiple bond