We have used x-ray reflectivity to study the coupling of surface and interface layering in a molecularly thin normal liquid [tetrakis(2-ethylhexoxy) silane (TEHOS)], as a function of temperature and film thickness. The best fits to the data were obtained with an electron density model that consists of a uniform density component superimposed upon molecular-scale density oscillations (layers). The two types of layer profiles were observed to vary with temperature from 187-286 K. The amount of material in the molecular layers increases as that in the uniform density layer decreases, with the onset of liquid-to-layered transition occurring at a total film thickness of ∼40 (about twice the bulk correlation length of TEHOS).
|Original language||English (US)|
|Journal||Physical Review E - Statistical, Nonlinear, and Soft Matter Physics|
|State||Published - Mar 14 2008|
ASJC Scopus subject areas
- Statistical and Nonlinear Physics
- Statistics and Probability
- Condensed Matter Physics