title: Pore size dependent dynamics of confined water probed by FIR spectroscopy.
abstract: We measured the FIR (Far Infrared) absorbance of a series of organic hydrated sub-nanopores (i.e. pores of the size of several A) containing confined water. Our results show that the FIR frequency region between 400 and 570 cm(-1) is sensitive to the differences in water mobility. The absorbance of these compounds was significantly higher than that of chemically similar anhydrous or non-porous hydrated compounds in the same region. Moreover, changes in the water dynamics inside the hydrated pores were found and characterized by their temperature dependent studies in the range from -5 to 20 degrees C. Upon increasing the temperature, water confined in narrow pores shows a small increase in FIR absorbance, while less confined water molecules inside larger pores exhibit a higher increase in absorbance, resembling more what has been observed for bulk water.
authors.affiliation: Instituto de Investigaciones Químicas, Avda. Américo Vespucio, 49, 41092 Seville, Spain. natalia.perez@iiq.csic.es
authors.forename: Natalia
authors.initials: N
authors.lastname: Pérez-Hernández
authors.forename: Trung Quan
authors.initials: TQ
authors.lastname: Luong
authors.forename: Cirilo
authors.initials: C
authors.lastname: Pérez
authors.forename: Julio D
authors.initials: JD
authors.lastname: Martín
authors.forename: Martina
authors.initials: M
authors.lastname: Havenith
mesh_terms: D006860:Hydrogen Bonding; D016062:Porosity; D017550:Spectroscopy, Fourier Transform Infrared; D013696:Temperature; D014867:Water / Q000737:chemistry*
chemical_list: D014867:Water