Electrostatically-bound Olefin Complexes

The olefin complexes discussed above could either be classified as belonging to the DCD bonding scheme or metallacyclopropanes. Now we want to introduce yet another type of strongly bonded TM-olefin complex which is held together mainly by electrostatic interactions. 

The DCD bonding model of TM olefin complexes is supported by accurate quantum chemical calculations which quantify the amount of ligand - metal donation and metal ligand back-donation. The geometries and bond energies 

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