An experimental and theoretical investigation of the electronic structure of Pd and Pt bis(carbene) complexes

Abstract

Photoelectron spectra and density functional calculations are reported for M(CN₂R₂C₂H₂)₂ (M = Pd, Pt); bonding occurs predominantly through ς donation from the carbene lone pairs into a metal (d_z2 + s) hybrid; the corresponding (d_z2 – s) is destabilised with respect to the other metal orbitals; there is little evidence for π bonding and the carbene π orbitals are essentially unperturbed on complexation.

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