Die elektronenstruktur der ethen-nickel π-komplexe the electronic structure of ethylene nickel π-complexes

Nickel(0)-olefine π-complexes such as Ni(C₂H₄)₃ and Ni(C₂H₄)(PR₃)₂ 6] prepared by conventional ligand replacement reaction are diamagnetic and stable up to room temperature. Similar π-complexes e.g. Ni(C₂H₄) _n (withn = 1, 2 or 3) generated by cryo-condensation technique 3] may exist in a paramagnetic state which derives from the triplet ground state of the atomic nickel. The stability of (η²-ethylene) nickel has been explained byab initio-MO calculations relating the energies of the complexes to different terms (¹ S and³ F) of the nickel atom.