title: Atomic interactions in ethylenebis(1-indenyl)zirconium dichloride as derived by experimental electron density analysis.
abstract: A topological analysis of the experimental electron density in racemic ethylenebis(1-indenyl)zirconium dichloride, C20H16Cl2Zr, measured at 100 (1) K, has been performed. The atomic charges calculated by the numerical integration of the electron density over the zero-flux atomic basins demonstrate the charge transfer of 2.25 e from the Zr atom to the two indenyl ligands (0.19 e to each) and two Cl atoms (0.93 e to each). All the atomic interactions were quantitatively characterized in terms of the electron density and the electronic energy-density features at the bond critical points. The Zr-C2 bond paths significantly curved towards the C1-C2 bond were found; no other bond paths connecting the Zr atom and indenyl ligand were located. At the same time, the pi-electrons of the C1-C2 bond are significantly involved in the metal-ligand interaction. The electron density features indicate that the indenyl coordination can be approximately described as eta1 with slippage towards eta2. The ;ligand-opposed' charge concentrations around the Zr atom were revealed using the Laplacian of the electron density and the one-particle potential; they were linked to the orbital representations. Bonds in the indenyl ligand were characterized using the Cioslowski-Mixon bond-order indices calculated directly from the experimental electron density.
authors.affiliation: L. Ya. Karpov Institute of Physical Chemistry, Vorontsovo Pole 10, Moscow 103064, Russia.
authors.forename: Adam I
authors.initials: AI
authors.lastname: Stash
authors.forename: Kiyoaki
authors.initials: K
authors.lastname: Tanaka
authors.forename: Kazunari
authors.initials: K
authors.lastname: Shiozawa
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Makino
authors.forename: Vladimir G
authors.initials: VG
authors.lastname: Tsirelson