A new approach for measuring neutron reflection from a liquid/liquid interface

Abstract
We report the design and application of a new general sample cell for structural studies at a buried liquid/liquid interface using neutron reflectometry. This new approach is suitable both for volatile and for non-volatile liquids. The neutron-reflectivity spectra from interfaces comprising a stable roughly 16 000 Å thick cyclohexane layer and a roughly 8000 Å thick hexadecane layer trapped between bulk silicon and water phases are presented. The roughness determined at the oil/water interfaces compares reasonably well with the estimated capillary wave roughness.