Portrait of Rachel O'Brien

Rachel O’Brien

Assistant Professor


171 EWRE, 1351 Beal Ave, Ann Arbor, MI 48109

  • Ph.D., (Chemistry), University of California, Berkeley 2012
  • BA, (Chemistry) Grinnell College 2004

The O’Brien research group focuses on the sources, composition, and fate of atmospheric organic material both indoors and outdoors. We measure organic aerosol composition, especially as a function of aerosol size, and we evaluate how aerosol particles will evolve in terms of their chemical and physical properties as they are transported in the air. We also study organic surface films that form when aerosol particles and gases deposit on different surfaces both indoors and outdoors. The overall goal of our research is a better understanding of the health impacts of the air we are breathing and the climate impacts of outdoor atmospheric aerosol particles. 

  • Monica Dibley, Aron Jaffe, Rachel E. O’Brien; “Molecular Insights into Dissolved Organic Matter in Natural Dew Water: Bio-grime Films on Leaf Surfaces”, submitted to ACS Earth and Space Chemistry,  2022, 6,3, 775-787.
  • Rachel E. O’Brien, Ying Li, Kristian J. Kiland, Erin Katz, Victor W. Or, Emily Legaard, Emma Q. Walhout, Corey Thrasher, Vicki H. Grassian, Peter F. DeCarlo, Allen K. Bertram, Manabu Shiraiwa; “Emerging investigator series: Chemical and Physical Properties of Organic Mixtures on Indoor Surfaces During HOMEChem”; Environmental Science: Processes and Impacts, 2021, 23, 559-568.
  • Lemai Vo, Emily Legaard, Corey Thrasher, Aron Jaffe, Giel Berden, Jonathan Martens, Jos Oomens, Rachel E. O’Brien; “UV/Vis and IRMPD Spectroscopic Analysis of the Absorption Properties of Methylglyoxal Brown Carbon”; ACS Earth and Space Chemistry, 2021, 5 (4), 910-919.
  • T. Braman, L. Dolvin, C. Thrasher, H. Yu, E. Q. Walhout, R. E. O’Brien; “Fresh versus Photo-recalcitrant Secondary Organic Aerosol: Effects of Organic Mixtures on Aqueous Photodegradation of 4-Nitrophenol”; Environ. Sci. Technol. Lett., 202, 7 (4), 248-253.
  • Andrew P. Ault, Vicki H. Grassian, Nicola Carslaw, Douglas B. Collins, Hugo Destaillats, D. James Donaldson, Delphine K. Farmer, Jose L. Jimenez, V. Faye McNeill, Glenn C. Morrison, Rachel E. O’Brien, Manabu Shiraiwa, Marina E. Vance, J. R. Wells, Wei Xiong;  Indoor Surface Chemistry, Developing a Molecular Picture of Reactions on Indoor Interfaces, Chem, 2020, 6 (12), 3203-3218.
  • V. W. Or, M. Wade, S. Patel, M. R. Alves, D. Kim, S. Schwab, H. Przelomski, R. E. O’Brien, D. Rim, R. L. Corsi, M. E. Vance, D. K. Farmer, V. H. Grassian; “Glass surface evolution following gas adsorption and particle deposition from indoor cooking events as probed by microspectroscopic analysis; Environmental Science: Processes & Impacts,2020, 22, 1698-1709.
  •  E. Q. Walhout, H. Yu, C. Thrasher, J. Shusterman, R. E. O’Brien; “Effects of Photolysis on the Chemical and Optical Properties of Secondary Organic Material Over Extended Timescales”; ACS Earth and Space Chem. 2019, 3, (7), 1226-1236.
  • E. Q. Walhout, S. E. Dorn, J. Martens, G. Berden, ­J. Oomens, P. Ha-Yeon CheongJ. H. Kroll,R.E. O’Brien; “Infrared Ion Spectroscopy of Environmental Organic Mixtures: Probing the Composition of a-Pinene Secondary Organic Aerosol”, Environmental Science and Technology, 2019, 53 (13), 7604-7612.
  • American Association for Aerosol Research
  • Sloan Foundation: Surface Consortium for Chemistry of the Indoor Environment
  • Phi Beta Kappa, 2004
  • NSF CAREER, 2021