Structure of thin, ordered cyclohexane films on metal surfaces

Abstract

The adsorption of multilayers of cyclohexane on Cu(111) has been studied by reflection absorption infrared spectroscopy (RAIRS) and electron energy loss spectroscopy (EELS) under controlled ultra-high vacuum conditions. These vibrational data reveal that at 95 K, the cyclohexane multilayers possess. Phase II structure but exist in polycrystalline domains of arbitrary size and orientation. After annealing to 135 K and re-cooling, a more ordered Phase II crystalline structure forms in which the Z-axes of all the unit cells are preferentially aligned along the surface normal. The growth and structure of the cyclohexane multilayers is found not to be dictated by the geometry of the crystal surface or details of monolayer adsorption. Multilayers on Pd(110) are very similar to those on Cu(111).