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A comparative study of the topology of the experimental electron density within 2 and 4e- donor alkyne complexes
Hanne Nuss1, Nicolas Claiser, Sébastien Pillet
1Laboratoire Cristallographie, Résonance Magnétique et Modélisations, UMR CNRS 7036, Faculté des Sciences et Technologies, Université de Lorraine, BP 70239, Boulevard des Aiguillettes, 54506 Vandoeuvre-lès-Nancy CEDEX, France.
Abstract:
A comparison of the topology of the experimental electron density, as revealed by high resolution X-ray diffraction, is provided for two prototypal transition metal alkyne complexes where the alkyne formally behaves as a 2 or 4e(-) donor. A higher value of the electron density ρ(r)(bcp) at the M(T)···C bond critical point (bcp), a lower value of ρ(r)(bcp) at the coordinated C≡C bcp, outwardly bent MC bond paths and a close to zero ellipticity for the C[triple bond, length as m-dash]C bond constitute the topological signature of a 4e(-) donor alkyne ligand.
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