An EXAFS investigation of the Lewis acids zirconium tetrachloride and cyclopentadienylzirconium trichloride in tetrahydrofuran solutions

Abstract

The 1 : 2 Lewis adducts of zirconium tetrachloride (ZrC1,) and cyclopentadienylzirconium trichloride (CpZrC13) with tetrahydrofuran (THF) have been studied in solutions by means of X-ray absorption spectroscopy. The organometallic complex CpZrCl,(THF), has in THF solution a structure similar to the known crystallographic solid state structure. In solution the average zirconium-carbon distance is 0.06 A longer, and the average Zr-oxygen distance as well as the average Zr-chlorine distance are 0.05 A shorter than in the solid state. In the inorganic complex ZrCl,(THF)* the zirconium-oxygen distance is short (2.22 A), and the trans influence difference between chloride and tetrahydrofuran ligands gives two experimentally separable zirconium-chlorine distances (2.39 A and 2.49 A).