title: Study of percolation and clustering in supercritical water-CO2 mixtures.
abstract: The microscopic structure of supercritical water-CO(2) mixture is investigated by neutron diffraction experiments exploiting the isotopic HD substitution. The investigated water reach mixtures are in the liquidlike region of the phase diagram, according to the behavior of the radial distribution functions, yet a reduction of the average number of hydrogen bonds, compared to equivalent states of pure water, is found. As a consequence, the average dimension of water clusters is reduced and the system stays below the percolation threshold. These results, along with the shift of the main peaks of the site-site radial distribution functions, suggest that the excess volume in these supercritical mixtures is likely associated with the CO(2) solvation shell.
authors.affiliation: Dipartimento di Fisica E. Amaldi, Università degli Studi Roma Tre, Via della Vasca Navale 84, 00146 Roma, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Botti
authors.forename: F
authors.initials: F
authors.lastname: Bruni
authors.forename: R
authors.initials: R
authors.lastname: Mancinelli
authors.forename: M A
authors.initials: MA
authors.lastname: Ricci
authors.forename: F
authors.initials: F
authors.lastname: Lo Celso
authors.forename: R
authors.initials: R
authors.lastname: Triolo
authors.forename: F
authors.initials: F
authors.lastname: Ferrante
authors.forename: A K
authors.initials: AK
authors.lastname: Soper