Dissociation dynamics of transient species, three-body reaction dynamics, novel mass-spectrometric methods
University of California, Berkeley
Johns Hopkins University
University of Rome La Sapienza
University of Melbourne
Kurt Shuler Scholar,
University of California, Berkeley
Awards and Academic Honors
UCSD Diversity Champion Award
ACS Division of Physical Chemistry Award in Experimental Chemistry
Fellow, American Physical Society
Alfred P. Sloan Research Fellowship
Camille Dreyfus Teacher-Scholar Award
David and Lucile Packard Fellowship in Sciences and Engineering
Camille and Henry Dreyfus New Faculty Award
Transient species, including reactive free radicals and molecular clusters, play central roles in governing the chemical behavior of complex systems. We seek to characterize these species by using a variety of techniques, including mass spectrometry, photoelectron and photofragment spectroscopies and the measurement of scattering cross-sections. These experiments provide critical tests of modern electronic structure and dynamics calculations, and in the case of three-body dissociation, new types of experimental data on the dynamics of these processes.
Our studies of reactive free-radicals, transition-states and multi-body dissociation dynamics use the photoelectron-photofragment coincidence technique developed here. These experiments are carried out using fast, mass-selected anion beams with short-pulse tunable laser photodetachment. The photoelectron kinetic energy and angle of recoil is measured using imaging techniques, which determines the internal energy in the neutral molecule or cluster under study. If the neutral is unstable and dissociates, then the kinetic energy and angular distributions of the products are recorded using time- and position-sensitive detectors. Analysis of these experiments is carried out in conjunction with ab initio electronic structure, Franck-Condon and dynamics calculations.One application of these techniques is to the dynamics of hydroxyl radical reactions important in combustion and atmospheric processes. Another important research focus has been reactive organic intermediates such as alkoxides and alkoxy radicals.
Our newest apparatus is under construction - the aerosol impact machine. This apparatus will allow us to trap and age charged nanoparticles, measure the mass and charge of individual particles, and then accelerate the single particles for hypervelocity impact on a diamond surface. The controllable vaporization that will ensue will allow determination of the depth profile of compounds in aerosols and other nanoparticles.
Primary Research Area
Atmospheric and Environmental
Appointed Chair of the Chancellor’s Diversity Council, coordinating communication of the broader campus community with Assoc. Chancellor and Chief Diversity Officer and the Chancellor.
Hosted visit by high school students from San Marcos High School to my lab.
As Department Chair, established Departmental Diversity and Outreach Committee.
Appointed to the new Campus Council on Equity and Inclusion.
PI, Graduate Assistantships in Areas of National Need (GAANN) grant, supporting 14 Ph.D. students across the Department.
Experiment and Theory for the Benchmark Reaction F + H2O -> HF + OH
- Otto R, Ma J, Ray AW, Daluz JS, Li J, Guo H, Continetti RE, "Imaging dynamics on the F + H2O -> HF + OH potential energy surfaces from wells to barriers.", Science, 2014, Vol. 343, Issue 6169, 396-9
- Adamson BD, Coughlan NJ, Continetti RE, Bieske EJ, "Changing the shape of molecular ions: photoisomerization action spectroscopy in the gas phase.", Phys Chem Chem Phys, 2013, Vol. 15, Issue 24, 9540-8
- Mann JE, Xie Z, Savee JD, Bowman JM, Continetti RE, "Vibrational excitation and product branching ratios in dissociation of the isotopologs of H3O: experiment and theory.", J Phys Chem A, 2013, Vol. 117, Issue 32, 7256-66
- Poad BL, Ray AW, Continetti RE, "Dissociative photodetachment of the ethoxide anion and stability of the ethoxy radical CH3CH2O•.", J Phys Chem A, 2013, Vol. 117, Issue 46, 12035-41
- Johnson CJ, Harding ME, Poad BL, Stanton JF, Continetti RE, "Electron affinities, well depths, and vibrational spectroscopy of cis- and trans-HOCO.", J Am Chem Soc, 2011, Vol. 133, Issue 49, 19606-9
- New insight into the barrier governing CO2 formation from OH + CO, with C.J. Johnson, B.L.J. Poad and B.B. Shen, J. Chem. Phys. 134, 171106 (2011).
- Photoelectron-photofragment coincidence spectroscopy in a cryogenically cooled electrostatic ion beam trap, with C.J. Johnson, B.B. Shen and B.L.J. Poad, Rev. Sci. Instrum. 82, 105105 (2011).
- Production of vibrationally excited H2O from charge exchange of H3O+ with cesium, with J.E. Mann, Z. Xie, J.D. Savee and J.M. Bowman, J. Chem. Phys. 130, 041102 (2009)
- The role of excited-state topology in three-body dissociation of sym-triazine, with J.D. Savee, V. A. Mozhayskiy, J.E. Mann and A.I. Krylov, Science, 321, 826 (2008)
- Alignment of a molecular anion via a shape resonance in near-threshold photodetachment, with Z. Lu, Phys. Rev. Lett. 99, 113005 (2007)
- Three-body dissociation dynamics of the low-lying Rydberg states of H3 and D3, with C.M. Laperle, J.E. Mann and T.G. Clements, Phys. Rev. Lett. 93, 153202 (2004)