Vapor adsorption on mica and silicon: Entropy effects, layering, and surfaces forces

Journal Article · Thu Apr 16 00:00:00 EDT 1992 · Journal of Physical Chemistry

DOI:https://doi.org/10.1021/j100187a040· OSTI ID:437086

Beaglehole, D ^[1]; Christenson, H K ^[2]

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1. Victoria Univ. of Wellington (New Zealand)
2. Australian National Univ., Canberra (Australia)

Using an angle-averaging, refractive-index-matching ellipsometric technique, absorption isotherms of n-pentane, cyclohexane, tetrachloromethane, and OMCTS are measured. OMCTS on silicon has a different isotherm than the other nonpolar liquids, which are all very similar. Up to half a statistical monolayer thickness, all isotherms except OMCTS are smooth and linear. At separations below 2 nm, none of the isotherms agree with the Lifshitz of van der Waals forces. If the substrates are smooth and homogeneous, structural effects may be present in many liquid adsorbed films at room temperature. 69 refs., 11 figs.

• Sponsoring Organization: USDOE
• OSTI ID: 437086
• Journal Information: Journal of Physical Chemistry, Journal Name: Journal of Physical Chemistry Journal Issue: 8 Vol. 96; ISSN JPCHAX; ISSN 0022-3654
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
40 CHEMISTRY
ADSORPTION ISOTHERMS
CYCLOHEXANE
ENTROPY
FREE ENERGY
METHANE
MICA
PENTANE
SILICON
SILOXANES
SURFACE FORCES
WATER