Pore size dependent dynamics of confined water probed by FIR spectroscopyElectronic supplementary information (ESI) available: Description and analytical data of the compounds. See DOI: 10.1039/c000985g

• Main Authors: Pérez-Hernández, Natalia, Luong, Trung Quan, Pérez, Cirilo, Martín, Julio D, Havenith, Martina
• Format: Journal Article
• Language: English
• Published: 23.06.2010
• ISSN: 1463-9076; 1463-9084
• DOI: 10.1039/c000985g

We measured the FIR (Far Infrared) absorbance of a series of organic hydrated sub-nanopores ( i.e. pores of the size of several ) 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 °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. FIR spectroscopy is used to monitor the differences of water dynamics in organic pores depending exclusively on their size.