title: Intracrystalline diffusivities and surface permeabilities deduced from transient concentration profiles: methanol in MOF manganese formate.
abstract: The intracrystalline concentration profiles during molecular uptake of methanol by an initially empty, single crystal of microporous manganese(II) formate (Mn(HCO2)2), representing an ionic inorganic-organic hybrid within the MOF family, are monitored by interference microscopy. Within these profiles, a crystal section could be detected where over the total of its extension ( approximately 2 microm x 50 microm x 30 microm) molecular uptake ideally followed the pattern of one-dimensional diffusion. Analysis of the evolution of intracrystalline concentration in this section directly yields the permeability of the crystal surface and the intracrystalline diffusivity as a function of the concentration of the total range of 0 <or= theta <or= 0.57 covered in the experiments. Within this range, the surface permeability is found to increase by 1 order of magnitude, while, within the limits of accuracy (+/-30%), the transport diffusivity remains constant, thus reflecting the properties of the lattice gas model.
authors.affiliation: Universität Leipzig, Linnéstr. 5, 04103 Leipzig, Germany.
authors.forename: Pavel V
authors.initials: PV
authors.lastname: Kortunov
authors.forename: Lars
authors.initials: L
authors.lastname: Heinke
authors.forename: Mirko
authors.initials: M
authors.lastname: Arnold
authors.forename: Yannic
authors.initials: Y
authors.lastname: Nedellec
authors.forename: Deborah J
authors.initials: DJ
authors.lastname: Jones
authors.forename: Jürgen
authors.initials: J
authors.lastname: Caro
authors.forename: Jörg
authors.initials: J
authors.lastname: Kärger