Diketone P-diketones

Lanthanide(III) ions form three distinct types of complexes with 1,3-diketones (p-diketones) (a) tris complexes with a metal-to-ligand ratio of 1 3, (b) Lewis-base adducts of tris complexes, and (c) tetrakis complexes with a metal-to-ligand ratio of 1 4 (Binnemans, 2005a). It is very difficult to obtain pure monomeric tris complexes, because the coordination number of the lanthanide ion in this type of compounds is six and this is too low for saturation of the first coordination sphere of a trivalent lanthanide ion (except for tris complexes of very bulky 1,3-diketones). Therefore, most of the tris complexes form either dimeric (or even oligomeric or polymeric) complexes, or they form hydrates. The water molecules act as Lewis bases and by addition of... 

One of synthetic approaches for the iron nanoparticles is based on the widely used decomposition of iron pentacarbonyl [19, 361, 362], The novelty of the approach is the surfactant system used. Studies with a number of strongly bound surfactants have resulted in decreased magnetic response, due to surface oxidation, disturbing the electronic structure of the surface atoms, or some other mechanism. With this in mind, ones chose to work with a weak surfactant, a p-diketone. P-diketones do have a history as adhesion promoters in bonds between metals and polymers [363], The limited reactivity of p-diketones is as an advantage the P-diketone is much weaker oxidizer than carboxylic acids or alcohols and will not oxidize iron, it is not as nucleophilic as phosphines, yet it is known to be capable of chelating iron. 

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