Heavy donor atoms

Also in the divalent state, Pd and Pt show the class-b characteristic of preferring CN and ligands with nitrogen or heavy donor atoms rather than oxygen or fluorine. Platinum(IV) by contrast is more nearly class-a in character and is frequently reduced to Pt by P- and Aj-donor ligands. The organometallic chemistry of these metals is rich and varied and that involving unsaturated hydrocarbons is the most familiar of its type. 

Complexes of open chain tetradentate ligands containing heavy donor atoms. C. A. McAuliffe, Adv. Inorg. Chem. Radiochem., 1975,17,165-187 (58). 

Complexes of Open-Chain Tetradenate Ligands Containing Heavy Donor Atoms... 

Soft acceptors such as Cu+, Tl, Hg2 are easily polarizable and tend to react with heavy donor atoms 14>1S) ... 

COMPLEXES OF OPEN-CHAIN TETRADENTATE LIGANDS CONTAINING HEAVY DONOR ATOMS... 

Chemical shifts for some representative platinum compounds are given in Table 2. The order of ligands in their effect on dp, is similar to that on other well-studied transition metals (e.g. Co, ° Rh). In particular, ligands with heavy donor atoms tend to cause increased shielding of the metal nucleus so that, for example, the shielding increases from CD to Br to I . As discussed above for W(II) compounds, this may be understood in terms of the heavier donor atoms having a greater effect on r and C in Equation [1]. 

Heavy Donor Atoms in the Silicon Coordination Sphere... 

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