title: The use of second-harmonic generation to study diffusion through films under a liquid phase.
abstract: Knowledge of the diffusion of chemicals through buried films is important for a wide variety of systems--from sensing to drug delivery. Herein, we show that second-harmonic generation (SHG) can be used to follow the diffusion through a thin film buried under a liquid in situ. More specifically, the diffusion of 4-(4-diethylaminostyryl)-1-methylpyridinium iodide through zeolite precursor films of different thickness is followed. The diffusion coefficients are calculated according to Fick's law.
authors.affiliation: Center for Surface Chemistry and Catalysis, K.U.Leuven, Kasteelpark 23, Box 2461, 3001 Leuven, Belgium. monique.vanderveen@biw.kuleuven.be
authors.forename: Monique A
authors.initials: MA
authors.lastname: van der Veen
authors.forename: Marjan
authors.initials: M
authors.lastname: De Roeck
authors.forename: Ivo F J
authors.initials: IF
authors.lastname: Vankelecom
authors.forename: Dirk E
authors.initials: DE
authors.lastname: De Vos
authors.forename: Thierry
authors.initials: T
authors.lastname: Verbiest