title: Properties of water confined in ionic liquids.
abstract: The varying states of water confined in the nano-domain structures of typical room temperature ionic liquids (ILs) were investigated by (1)H NMR and by measurements of self-diffusion coefficients while systematically varying the IL cations and anions. The NMR peaks for water in BF4-based ILs were clearly split, indicating the presence of two discrete states of confined water (H2O and HOD). Proton and/or deuterium exchange rate among the water molecules was very slowly in the water-pocket. Notably, no significant changes were observed in the chemical shifts of the ILs. Self-diffusion coefficient results showed that water molecules exhibit a similar degree of mobility, although their diffusion rate is one order of magnitude faster than that of the IL cations and anions. These findings provide information on a completely new type of confinement, that of liquid water in soft matter.
authors.affiliation: Department of Environmental Engineering for Symbiosis, Soka University, 1-236 Tangi, Hachioji, Tokyo, 192-8577, Japan.
authors.forename: Koji
authors.initials: K
authors.lastname: Saihara
authors.affiliation: Department of Applied Chemistry, National Defense Academy, 1-10-20 Hashirimizu, Yokosuka, Kanagawa, 239-8686, Japan.
authors.forename: Yukihiro
authors.initials: Y
authors.lastname: Yoshimura
authors.affiliation: Department of Environmental Engineering for Symbiosis, Soka University, 1-236 Tangi, Hachioji, Tokyo, 192-8577, Japan.
authors.forename: Soichi
authors.initials: S
authors.lastname: Ohta
authors.affiliation: Department of Environmental Engineering for Symbiosis, Soka University, 1-236 Tangi, Hachioji, Tokyo, 192-8577, Japan.
authors.forename: Akio
authors.initials: A
authors.lastname: Shimizu