title: Pressure cell for investigations of solid-liquid interfaces by neutron reflectivity.
abstract: We describe an apparatus for measuring scattering length density and structure of molecular layers at planar solid-liquid interfaces under high hydrostatic pressure conditions. The device is designed for in situ characterizations utilizing neutron reflectometry in the pressure range 0.1-100 MPa at temperatures between 5 and 60 °C. The pressure cell is constructed such that stratified molecular layers on crystalline substrates of silicon, quartz, or sapphire with a surface area of 28 cm(2) can be investigated against noncorrosive liquid phases. The large substrate surface area enables reflectivity to be measured down to 10(-5) (without background correction) and thus facilitates determination of the scattering length density profile across the interface as a function of applied load. Our current interest is on the stability of oligolamellar lipid coatings on silicon surfaces against aqueous phases as a function of applied hydrostatic pressure and temperature but the device can also be employed to probe the structure of any other solid-liquid interface.
authors.affiliation: Angewandte Physikalische Chemie, Universität Heidelberg, Heidelberg, Germany.
authors.forename: Martin
authors.initials: M
authors.lastname: Kreuzer
authors.forename: Thomas
authors.initials: T
authors.lastname: Kaltofen
authors.forename: Roland
authors.initials: R
authors.lastname: Steitz
authors.forename: Beat H
authors.initials: BH
authors.lastname: Zehnder
authors.forename: Reiner
authors.initials: R
authors.lastname: Dahint
mesh_terms: D004134:Dimyristoylphosphatidylcholine / Q000737:chemistry; D033363:Neutron Diffraction / Q000295:instrumentation*; D011312:Pressure
chemical_list: D004134:Dimyristoylphosphatidylcholine