Skip to main content
Skip to main menu Skip to spotlight region Skip to secondary region Skip to UGA region Skip to Tertiary region Skip to Quaternary region Skip to unit footer


Photochemical Synthesis and Spectroscopy of Polycyclic Aromatic Hydrocarbon Dimers

Ian Webster
Ian Webster
Graduate Student, Department of Chemistry
University of Georgia
Physical Seminar

Laser desorption time-of-flight mass spectrometry (LD-ToF-MS) experiments on pressed-pellet samples of polycyclic aromatic hydrocarbons (PAHs) produce covalently-bonded dimers at masses (m/z) of 2M-2 and 2M-4 (where M is the parent mass). Through replication of these LD-ToF-MS conditions at higher throughput, PAH dimers have been produced and collected in milligram quantities. For collected samples of pyrene, perylene, and coronene, differential sublimation has isolated the dimer sample from residual monomers. After confirmation of the purification using LD-ToF-MS, the samples are analyzed using a variety of spectroscopic methods, including UV-Vis, IR, and Raman spectroscopy. Computational studies on dimer samples have been done using density functional theory with the CAM-B3LYP method at the def2TZV level of theory. These calculations were calibrated and checked by comparison with the monomer samples and used to determine the lowest energy dimer structures. The comparison of simulated and experimental spectra allows determination of the most prevalent structures for the PAH dimers.

Support Us

We appreciate your financial support. Your gift is important to us and helps support critical opportunities for students and faculty alike, including lectures, travel support, and any number of educational events that augment the classroom experience. Click here to learn more about giving.

Every dollar given has a direct impact upon our students and faculty.

Got More Questions?

Undergraduate inquiries: 

Registration and credit

AP Credit, Section Changes, Overrides,

Graduate inquiries:

Contact Us!

Assistant to the Department Head: Donna Spotts, 706-542-1919 

Main office phone: 706-542-1919 

Main Email:

Head of Chemistry: Prof. Jason Locklin