Report

First Solvation Shell of the Cu(II) Aqua Ion: Evidence for Fivefold Coordination

+ See all authors and affiliations

Science  02 Feb 2001:
Vol. 291, Issue 5505, pp. 856-859
DOI: 10.1126/science.291.5505.856

You are currently viewing the abstract.

View Full Text

Abstract

We determined the structure of the hydrated Cu(II) complex by both neutron diffraction and first-principles molecular dynamics. In contrast with the generally accepted picture, which assumes an octahedrally solvated Cu(II) ion, our experimental and theoretical results favor fivefold coordination. The simulation reveals that the solvated complex undergoes frequent transformations between square pyramidal and trigonal bipyramidal configurations. We argue that this picture is also consistent with experimental data obtained previously by visible near-infrared absorption, x-ray absorption near-edge structure, and nuclear magnetic resonance methods. The preference of the Cu(II) ion for fivefold instead of sixfold coordination, which occurs for other cations of comparable charge and size, results from a Jahn-Teller destabilization of the octahedral complex.

  • * To whom correspondence should be addressed. E-mail: Alfredo.Pasquarello{at}epfl.ch

View Full Text