Abstract
This work compares the extent of reversibility and the thermodynamics of adsorption (K ads , ΔG° ads ) of room-temperature vapors of common environmentally relevant monoterpenes (α-pinene, β-pinene, limonene, and 3-carene) and industrially relevant cyclic and acyclic non-terpene hydrocarbons (cyclohexane, hexane, octane, and cyclooctane) to fused silica surfaces. Vibrational sum frequency generation spectroscopy carried out in the C-H stretching region shows negligible surface coverage-dependent changes in the molecular orientation of all species surveyed except for cyclohexane. The group of monoterpenes studied here distinctly exhibits partially reversible adsorption to fused silica surfaces compared to the group of non-terpene hydrocarbons, demonstrating a link between molecular structure and adsorption thermodynamics. The standard Gibbs free energy of adsorption is nonlinearly correlated with the equilibrium vapor pressure of the compounds surveyed.
| Original language | English (US) |
|---|---|
| Article number | 074701 |
| Journal | Journal of Chemical Physics |
| Volume | 150 |
| Issue number | 7 |
| DOIs | |
| State | Published - Feb 21 2019 |
Funding
This work was supported by the National Science Foundation (NSF) under Grant No. CHE-1607640. H.M.C. gratefully acknowledges an NSF Graduate Research fellowship. F.M.G. gratefully acknowledges a Friedrich Wilhelm Bessel Prize from the Alexander von Humboldt Foundation. This work was supported by the National Science Foundation (NSF) under Grant No. CHE-1607640. H.M.C. gratefully acknowledges an NSF Graduate Research fellowship. F.M.G. gratefully acknowledges a Friedrich Wilhelm Bessel Prize from the Alexander von Humboldt Foundation. The authors declare no competing financial interest.
ASJC Scopus subject areas
- General Physics and Astronomy
- Physical and Theoretical Chemistry