title: Inelastic neutron scattering study of water in hydrated LTA-type zeolites.
abstract: The vibrational dynamics of water molecules encapsulated in synthetic Na-A and Mg-exchanged A zeolites were studied versus temperature by inelastic neutron scattering (INS) measurements (30-1200 cm(-1)) as a function of the induced ion-exchange percentage by using the indirect geometry tof spectrometer TOSCA at the ISIS pulse neutron facility (RAL, UK). The experimental INS spectra were compared with those of ice Ih to characterize the structural changes induced by confinement on the H2O hydrogen-bonded network. We observed, after increasing the Mg2+ content, a tendency of water molecules to restore the bulklike arrangements together with more hindered dynamics. These results are confirmed by the analysis of the evaluated one-phonon amplitude-weighted proton vibrational density of states aimed, in particular, to follow the evolution of the water molecules librational mode region.
authors.affiliation: Dipartimento di Fisica, Università di Messina, C.da Papardo, S.ta Sperone 31, P.O. BOX 55, 98166 Messina, Italy.
authors.forename: Carmelo
authors.initials: C
authors.lastname: Corsaro
authors.forename: Vincenza
authors.initials: V
authors.lastname: Crupi
authors.forename: Domenico
authors.initials: D
authors.lastname: Majolino
authors.forename: Stewart F
authors.initials: SF
authors.lastname: Parker
authors.forename: Valentina
authors.initials: V
authors.lastname: Venuti
authors.forename: Ulderico
authors.initials: U
authors.lastname: Wanderlingh