title: An unusual example of hypervalent silicon: a five-coordinate silyl group bridging two palladium or nickel centers through a nonsymmetrical four-center two-electron bond.
abstract: Pd and Ni dimers supported by PSiP ligands in which two hypervalent five-coordinate Si atoms bridge the two metal centers are reported. Crystallographic characterization revealed a rare square-pyramidal geometry at Si and an unusual asymmetric M2 Si2 core (M=Pd or Ni). DFT calculations showed that the unusual structure of the core is also found in a model in which the phosphine and Si centers are not part of a pincer group, thus indicating that the observed geometry is not imposed by the PSiP ligand. NBO analysis showed that an asymmetric four-center two-electron (4c-2e) bond stabilizes the hypervalent Si atoms in the M2 Si2 core.
authors: Centre for Theoretical and Computational Chemistry, Department of Chemistry, University of Oslo, P.O. Box 1033, Blindern, 0315 Oslo (Norway); Institute of Chemical Research of Catalonia (ICIQ), Avgda Països Catalans, 16, 43007 Tarragona (Spain). ainara.nova@kjemi.uio.no.
authors: Ainara
authors: A
authors: Nova
authors: Hee-Won
authors: HW
authors: Suh
authors: Timothy J
authors: TJ
authors: Schmeier
authors: Louise M
authors: LM
authors: Guard
authors: Odile
authors: O
authors: Eisenstein
authors: Nilay
authors: N
authors: Hazari
authors: Feliu
authors: F
authors: Maseras
keywords: electronic structure; four-center two-electron bonds; hypervalent silicon; nickel; palladium