PAHs on HOPG_revised.pdf (752.55 kB)
A TPD and RAIRS comparison of the low temperature behavior of benzene, toluene, and xylene on graphite
journal contribution
posted on 2023-06-09, 15:33 authored by Tara L Salter, James StubbingJames Stubbing, Lorna Brigham, Wendy BrownWendy BrownThe first comparative study of the surface behavior of four small aromatic molecules, benzene, toluene, p-xylene, and o-xylene, adsorbed on graphite at temperatures =30 K, is presented. Intermolecular interactions are shown to be important in determining the growth of the molecules on the graphite surface at low (monolayer) exposures. Repulsive intermolecular interactions dominate the behavior of benzene and toluene. By contrast, stronger interactions with the graphite surface are observed for the xylene isomers, with islanding observed for o-xylene. Multilayer desorption temperatures and energies increase with the size of the molecule, ranging from 45.5 to 59.5 kJ mol-1 for benzene and p-xylene, respectively. Reflection absorption infrared spectroscopy gives insight into the effects of thermal processing on the ordering of the molecules. Multilayer benzene, p-xylene, and o-xylene form crystalline structures following annealing of the ice. However, we do not observe an ordered structure for toluene in this study. The ordering of p-xylene shows a complex relationship dependent on both the annealing temperature and exposure.
Funding
Evolution of ices: From molecular cloud to ocean; G1613; STFC-SCIENCE AND TECHNOLOGY FACILITIES COUNCIL; ST/M000869/1
History
Publication status
- Published
File Version
- Accepted version
Journal
The Journal of Chemical PhysicsISSN
0021-9606Publisher
American Institute of PhysicsExternal DOI
Issue
164705Volume
149Page range
1-11Department affiliated with
- Chemistry Publications
Full text available
- Yes
Peer reviewed?
- Yes
Legacy Posted Date
2018-10-18First Open Access (FOA) Date
2018-10-18First Compliant Deposit (FCD) Date
2018-10-17Usage metrics
Categories
No categories selectedKeywords
Licence
Exports
RefWorks
BibTeX
Ref. manager
Endnote
DataCite
NLM
DC