Dibble Group Web Page

     Experimental studies employed lasers to probe for stable and transient species. Both reaction kinetics and the spectroscopy of new species have been studied using laser-induced fluorescence (LIF). Cavity ringdown spectroscopy in the near infrared is also used. We carry out ab initio and density functional calculations to map out thermochemical kinetics and to explore and interpret the spectroscopy of as-yet uncharacterized species.  See the article about our computational work in Access, the magazine of the National Compuational Science Alliance.
 
 

   Theodore S. Dibble (tsdibble @syr.edu)

Jiajue Chai
Hongyi Hu
DA Murray (class of '09)
Nathan Phillips (Class of ’09)
Karen Schmitt
Jessie Wang (Class of ’09)
Yue Zeng

Dr. Pawel Cias, postdoc 2004-06. Now at the University of Innsbruck.
Lei Zhang, Ph.D. 2005, Now at Bristol Meyers Squibb
Wei Deng, Ph.D. 2002. Now working for Honeywell Specialty Materials.
Dr. Chuji Wang, postdoc 1998-2000,  Now atMississippi State University
Liat Shemesh, M.S. 1999.
 
 

Jennifer Dabrowski 2005 (Le Moyne College, currently at Boston College)
Trang Pham 2004 (Emory University, M.S. Public Health, Columbia University)
Dean Derbyshire 2003 (Le Moyne College. currently studying Optometry)
Karen Callahan 2003 (Ohio State University, currently at UC-Irvine)
 
 

1)   Electron Beams for Degradation of Airborne Pollutants. Irradiated air samples are analyzed by GC or GC-MS to determine the efficiency of destruction of the pollutant and to identify and quantify the degradation products. Kinetic modeling is used to understand factors controlling degradation efficiency. Spectroscopy (see below) will be used to measure radical concentrations and characterize the plasma.

2)   Cavity Ringdown Spectroscopy (CRDS) CRDS in the near-infrared is used to measure temperature and OH radical concentration in plasmas, both the electron beam discussed above and a variety of other non-thermal plasmas. This project is being carried out in collaboration with Dr. Chuji Wang at Mississippi State University.

3)   Alkoxy Radical Spectroscopy and Kinetics. Past work centered on alkoxy radicals from saturated alkanes, but is being extended to alkoxy radicals with various functional groups. We have a particular interest in b-hydroxy alkoxy radicals (e.g., HOCH2CH2O), which are both atmospherically important and possess intramolecular hydrogen bonds donated from the hydroxy group to the radical center.

4)    Computational studies of alkoxy and peroxy radicals from isoprene and related molecules.  About 500 Mtons of isoprene (2-methyl-1,3-butadiene) is emitted to the atmosphere each year, where it affects local and global ozone as well as aerosol production. Quantum chemistry is used to determine the atmospheric reaction pathways of alkoxy and peroxy radicals from this critical compound. An important aspect of these radicals is their intramolecular hydrogen bonding, which can lead to some double H-atom jumps.

5)  Computational studies of other radical chemistry. A number of topics of interest (peroxy radicals in combustion chemistry, solvation and surface effects on reactivity) will be investigated via quantum chemistry, variational transition state theory, and trajectory calculations on analytical or ab initio surfaces.