title: Equilibrium between 5- and 6-Fold Coordination in the First Hydration Shell of Cu(II).
abstract: The hydration structure dynamics of Cu(II) ion is characterized by a combination of classical molecular dynamics simulation and X-ray absorption near-edge spectroscopy. Previous experimental data have been analyzed on the basis of 5- or 6-fold first hydration structure, with a quite well-established equatorial structure. This 4-fold equatorial geometry has been our starting point to develop a simple but effective in silico model, which provides ab initio theoretical X-ray absorption spectra in very good agreement with the experimental data. Our results point out two equally populated 6- and 5-fold hydration structures with remarkable different water residence times of 5 and 98 ps, respectively, and a low free energy barrier between first and second hydration shell.
authors.affiliation: SCAI SuperComputing Applications and Innovation Department , Cineca Via dei Tizii, 6. 00185 Rome, Italy.
authors.forename: Giovanni
authors.initials: G
authors.lastname: Chillemi
authors.affiliation: Laboratori Nazionali di Frascati-INFN , Post Office Box 13, 00044 Frascati, Italy.
authors.forename: Elisabetta
authors.initials: E
authors.lastname: Pace
authors.affiliation: Dipartimento di Chimica, Università di Roma "La Sapienza" , Ple A. Moro 5, 00185 Rome, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: D'Abramo
authors.affiliation: Laboratori Nazionali di Frascati-INFN , Post Office Box 13, 00044 Frascati, Italy.
authors.forename: Maurizio
authors.initials: M
authors.lastname: Benfatto