Bonding in Organotransition Metal Compounds

1a Ligands which in the free state would be a radical (one unpaired electron)  

3 Linear NO, nitride (N), linear NNR, NS, NSe, P Ligands which can be subdivided into a combination of 1VE and 2VE donations e.g. Tj3-allyl, ri3-cyclopropenyl, bidentate alkenyls, acyls, carboxylates, dithiocarbamates, amidates, fi-diketonates, salicylates, glyoximates 

4 Dienes, including cyclobutadiene and heteroatom-substituted dienes, e.g. vinyl ketones 

3 The Bonding of Unsaturated Organic Ligands to a Metal Centre 

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