Study of electronic structure of tetrakis(μ2-acetato)-diaqua-di-copper(II) complex

Abstract

The nature of Cu-Cu interaction in tetrakis(μ2-Acetato)-diaquadi-copper(ii) complex has been studied by both experimental and theoretical treatments. A large experimental data set (CCD GEMINI R diffractometer, 387268 diffractions at 100 K, resolution of 0.39 A, an average redundancy of 30.6) was measured. The data reduction (CrysAlis [1]) gives a unique 12674 diffractions (RInt = 0.026, R(σ) = 0.006). Refinement with the XD package [2] gives R{ F } = 0.0187. In order to identify the systematic errors in the experimental data sets of structure factors, the new procedure for obtaining the theoretical structure factors at 100 K from the theoretical grid electron density has been developed. The electron density at grid points is evaluated by CRYSTAL06 software for periodic quantum-chemical calculations at B3LYP level of theory [3]. The distance between the discrete grid point and the closest particular atom is used as a criterion for assigning the temperature factor to each grid point. The procedure developed might enable us to obtain spin density distribution, too. This work has been supported by Slovak Grant Agency VEGA (project No. 1/0817/08) [1] Oxford Diffraction (2008). CrysAlis RED 171.32.15. Oxford Diffraction Ltd, Abingdon, Oxfordshire, England. [2] R. Dovesi et al.; CRYSTAL06 User’s Manual, University of Torino, Torino, 2006. [3] T. Koritsanszky et al.; XD, A Computer Program Package for Multipole Refinement and Analysis of Charge Densities from X-ray Diffraction Data. Freie Universitat Berlin. User Manual (2003).