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Greg

Greg A Kimmel

Chemical Physics & Analysis
Physicist
Pacific Northwest National Laboratory
PO Box 999
MSIN: J7-10
Richland, WA 99352

Biography

Dr. Greg Kimmel investigates thermal and non-thermal reactions at surfaces and interfaces. These reactions are important in a wide range of applications including catalysis, photocatalysis, radiation chemistry and waste processing. Since high-energy radiation typically produces numerous low-energy secondary electrons that are chemically active, the low-energy electrons (<100 eV) frequently play a dominant role in radiation chemistry. In addition, the presence of surfaces or interfaces modifies the reactions and processes compared to what occurs in the bulk. In photocatalysis, visible and/or UV photons are used to initiate a variety of reactions. However, a detailed understanding of the underlying physical and chemical processes is often lacking. Dr. Kimmel and his colleagues use surface science techniques to investigate thermal and non-thermal reactions at surfaces and interfaces. This work addresses several important issues, including the need to understand the relative importance of the primary excitation source compared to the secondary electrons it produces, energy transfer at surfaces and interfaces, and new reaction pathways at surfaces. Dr. Kimmel also investigates the structure of water films at interfaces. Understanding the structure of the water films provides a foundation for the development of a detailed understanding of the reactions at aqueous interfaces.

Research Interests

  • energetic processes at surfaces and interfaces in fields such as radiation chemistry, waste processing, and advanced materials synthesis.
  • the structure of water at interfaces
  • chemistry on oxide surfaces

Education and Credentials

  • Ph.D. Applied Physics, Cornell University, Thesis topic: Charge exchange processes for atoms and molecules scattering from metal surfaces.
  • B.S. Engineering Physics (with distinction), Cornell University

Affiliations and Professional Service

  • American Physical Society
  • American Chemical Society

Awards and Recognitions

PNNL Publications

2024

  • Kimmel G.A. 2024. "Isotope effects in supercooled H2O and D2O and a corresponding-states-like rescaling of the temperature and pressure." Journal of Chemical Physics 160, no. 19:Art. No. 194508. PNNL-SA-195941. doi:10.1063/5.0207719

2023

  • Adamsen K.C., N.G. Petrik, W. Dononelli, G.A. Kimmel, T. Xu, Z. Li, and L. Lammich, et al. 2023. "Origin of Hydroxyl Pair Formation on Reduced Anatase TiO2(101)." Physical Chemistry Chemical Physics 25, no. 19:13645-13653. PNNL-SA-178908. doi:10.1039/D3CP01051A
  • Kringle L.M., B.D. Kay, and G.A. Kimmel. 2023. "Dynamic Heterogeneity and Kovacs' Memory Effects in Supercooled Water." Journal of Physical Chemistry B 127, no. 17:3919-3930. PNNL-SA-182629. doi:10.1021/acs.jpcb.3c01465
  • Kringle L.M., B.D. Kay, and G.A. Kimmel. 2023. "Structural relaxation of water during rapid cooling from ambient temperatures." The Journal of Chemical Physics 159, no. 6:Art. No. 064509. PNNL-SA-184979. doi:10.1063/5.0157046
  • O'Connor C.R., M.F. Calegari Andrade, A. Selloni, and G.A. Kimmel. 2023. "Elucidating the Water-Anatase TiO2(101) Interface Structure Using Infrared Signatures and Molecular Dynamics." The Journal of Chemical Physics 159, no. 10:Art. No. 104707. PNNL-SA-189813. doi:10.1063/5.0161895

2022

  • Kringle L.M., W.A. Thornley, B.D. Kay, and G.A. Kimmel. 2022. "Isotope effects on the structural transformation and relaxation of deeply supercooled water." The Journal of Chemical Physics 156, no. 8:Art. No. 084501. PNNL-SA-168415. doi:10.1063/5.0078796
  • Petrik N.G., M.D. Baer, C.J. Mundy, and G.A. Kimmel. 2022. "Mixed molecular and dissociative water Adsorption on hydroxylated TiO2(110): An Infrared Spectroscopy and Ab Initio Molecular Dynamics Study." Journal of Physical Chemistry C 126, no. 51:21616-21627. PNNL-SA-178151. doi:10.1021/acs.jpcc.2c07063

2021

  • Kringle L.M., W.A. Thornley, B.D. Kay, and G.A. Kimmel. 2021. "Structural relaxation and crystallization in supercooled water from 170 to 260 K." Proceedings of the National Academy of Sciences (PNAS) 118, no. 14:e2022884118. PNNL-SA-158074. doi:10.1073/pnas.2022884118
  • Petrik N.G., Y. Wang, B. Wen, Y. Wu, R. Ma, A.P. Dahal, and F. Gao, et al. 2021. "Conversion of Formic Acid on Single- and Nano-Crystalline Anatase TiO2(101)." Journal of Physical Chemistry C 125, no. 14:7686-7700. PNNL-SA-159116. doi:10.1021/acs.jpcc.1c00571

2020

  • Deskins N.A., G.A. Kimmel, and N.G. Petrik. 2020. "Observation of molecular hydrogen produced from bridging hydroxyls on anatase TiO2(101)." The Journal of Physical Chemistry Letters 11, no. 21:9289-9297. PNNL-SA-155933. doi:10.1021/acs.jpclett.0c02735
  • Wang Y., B. Wen, A.P. Dahal, G.A. Kimmel, R.J. Rousseau, A. Selloni, and N.G. Petrik, et al. 2020. "Binding of Formic Acid on Anatase TiO2(101)." Journal of Physical Chemistry C 124, no. 37:20228-20239. PNNL-SA-153864. doi:10.1021/acs.jpcc.0c06031

2018

  • Petrik N.G., and G.A. Kimmel. 2018. "Electron-stimulated reactions in nanoscale water films adsorbed on (alpha)-Al2O3(0001)." Physical Chemistry Chemical Physics 20, no. 17:11634-11642. PNNL-SA-132648. doi:10.1039/C8CP01284A
  • Petrik N.G., P.I. Huestis, J. Laverne, A. Aleksandrov, T.M. Orlando, and G.A. Kimmel. 2018. "Molecular water adsorption and reactions on (alpha)-Al2O3(0001) and (alpha)-Alumina Particles." Journal of Physical Chemistry C 122, no. 17:9540-9551. PNNL-SA-132650. doi:10.1021/acs.jpcc.8b01969
  • Petrik N.G., R. Mu, A.P. Dahal, Z. Wang, A.I. Lyubinetsky, and G.A. Kimmel. 2018. "Diffusion and photon-stimulated desorption of CO on TiO2(110)." Journal of Physical Chemistry C 122, no. 27:15382-15389. PNNL-SA-133615. doi:10.1021/acs.jpcc.8b03418
  • Zhang X., P.I. Huestis, C.I. Pearce, J.Z. Hu, K. Page, L.M. Anovitz, and A. Aleksandrov, et al. 2018. "Boehmite and Gibbsite Nanoplates for the Synthesis of Advanced Alumina Products." ACS Applied Nano Materials 1, no. 12:7115-7128. PNNL-SA-139693. doi:10.1021/acsanm.8b01969

2017

  • Mu R., A.P. Dahal, Z. Wang, Z. Dohnalek, G.A. Kimmel, N.G. Petrik, and I.V. Lyubinetsky. 2017. "Adsorption and Photodesorption of CO from Charged Point-Defects on TiO2(110)." The Journal of Physical Chemistry Letters 8, no. 18:4565-4572. PNNL-SA-128233. doi:10.1021/acs.jpclett.7b02052

2016

  • Petrik N.G., G.A. Kimmel, M. Shen, and M.A. Henderson. 2016. "Quenching of Electron Transfer Reactions through Coadsorption: A Study of Oxygen Photodesorption from TiO2(110)." Surface Science 652. PNNL-SA-114433. doi:10.1016/j.susc.2015.12.038

2015

  • Petrik N.G., and G.A. Kimmel. 2015. "Reaction Kinetics of Water Molecules with Oxygen Vacancies on Rutile TiO2(110)." Journal of Physical Chemistry C 119, no. 40:23059-23067. PNNL-SA-111828. doi:10.1021/acs.jpcc.5b07526
  • Petrik N.G., M.A. Henderson, and G.A. Kimmel. 2015. "Insights into Acetone Photochemistry on Rutile TiO2(110). 1. Off-Normal CH3 Ejection from Acetone Diolate." Journal of Physical Chemistry C 119, no. 22:12262-12272. PNNL-SA-108620. doi:10.1021/acs.jpcc.5b02477
  • Petrik N.G., M.A. Henderson, and G.A. Kimmel. 2015. "Insights into Acetone Photochemistry on Rutile TiO2(110). 2. New Photodesorption Channel with CH3 Ejection along the Surface Normal." Journal of Physical Chemistry C 119, no. 22:12273-12282. PNNL-SA-108621. doi:10.1021/acs.jpcc.5b02478
  • Yoon Y., Y. Du, J.C. Garcia, Z. Zhu, Z. Wang, N.G. Petrik, and G.A. Kimmel, et al. 2015. "Anticorrelation between Surface and Subsurface Point Defects and the Impact on the Redox Chemistry of TiO2(110)." ChemPhysChem 16, no. 2:313-321. PNNL-SA-105906. doi:10.1002/cphc.201402599

2014

  • Lercher J.A., A.M. Appel, T. Autrey, R.M. Bullock, D.M. Camaioni, H.M. Cho, and D.A. Dixon, et al. 2014. "Multifunctional Catalysts to Synthesize and Utilize Energy Carriers." In Frontiers at the Interface between Homogeneous and Heterogeneous Catalysis, II, 207-219. Washington, District Of Columbia:U.S. Department of Energy, Office of Science. PNNL-SA-103068.
  • Petrik N.G., and G.A. Kimmel. 2014. "Probing the photochemistry of chemisorbed oxygen on TiO2(110) with Kr and other co-adsorbates." Physical Chemistry Chemical Physics 16, no. 6:2338-2346. PNNL-SA-98647. doi:10.1039/c3cp54195a
  • Petrik N.G., R.J. Monckton, S. Koehler, and G.A. Kimmel. 2014. "Distance-dependent radiation chemistry: Oxidation versus hydrogenation of CO in electron-irradiated H2O/CO/H2O ices." Journal of Physical Chemistry C 118, no. 47:27483-27492. PNNL-SA-105600. doi:10.1021/jp509785d
  • Petrik N.G., R.J. Monckton, S. Koehler, and G.A. Kimmel. 2014. "Electron-stimulated reactions in layered CO/H2O films: Hydrogen atom diffusion and the sequential hydrogenation of CO to methanol." Journal of Chemical Physics 140, no. 20:Article No. 204710. PNNL-SA-100690. doi:10.1063/1.4878658

2013

  • Petrik N.G., and G.A. Kimmel. 2013. "Multiple Non-Thermal Reaction Steps for the Photooxidation CO to CO2 on Reduced TiO2(110)." The Journal of Physical Chemistry Letters 4, no. 3:344-349. PNNL-SA-92421. doi:10.1021/jz302012j

2012

  • Du Y., N.G. Petrik, N.A. Deskins, Z. Wang, M.A. Henderson, G.A. Kimmel, and I. Lyubinetsky. 2012. "Hydrogen Reactivity on Highly-hydroxylated TiO2(110) Surfaces Prepared via Carboxylic Acid Adsorption and Photolysis." Physical Chemistry Chemical Physics. PCCP 14, no. 9:3066-3074. PNNL-SA-82616. doi:10.1039/C1CP22515D
  • Kimmel G.A., M.D. Baer, N.G. Petrik, J. VandeVondele, R.J. Rousseau, and C.J. Mundy. 2012. "Polarization- and Azimuth-Resolved Infrared Spectroscopy of Water on TiO2(110): Anisotropy and the Hydrogen-Bonding Network." The Journal of Physical Chemistry Letters 3, no. 6:778-784. PNNL-SA-85286. doi:10.1021/jz3001079
  • Lin X., Y. Yoon, N.G. Petrik, Z. Li, Z. Wang, V.A. Glezakou, and B.D. Kay, et al. 2012. "Structure and Dynamics of CO2 on Rutile TiO2(110)-1x1." Journal of Physical Chemistry C 116, no. 50:26322-26334. PNNL-SA-89052. doi:10.1021/jp308061j
  • Petrik N.G., and G.A. Kimmel. 2012. "Adsorption geometry of CO versus coverage on TiO2(110) from s- and p-polarized infrared spectroscopy." The Journal of Physical Chemistry Letters 3, no. 23:3425-3430. PNNL-SA-90608. doi:10.1021/jz301413v

2011

  • Petrik N.G., and G.A. Kimmel. 2011. "Electron- and hole-mediated reactions in UV -irradiated O2 adsorbed on reduced rutile TiO2(110)." Journal of Physical Chemistry C 115, no. 1:152-164. PNNL-SA-71556. doi:10.1021/jp108909p
  • Petrik N.G., and G.A. Kimmel. 2011. "Oxygen Photochemistry on TiO2(110): Recyclable, Photoactive Oxygen Produced by Annealing Adsorbed O2." The Journal of Physical Chemistry Letters 2, no. 21:2790-2796. PNNL-SA-82849. doi:10.1021/jz201225c

2010

  • Petrik N.G., and G.A. Kimmel. 2010. "Off-normal CO2 desorption from the photooxidation of CO on reduced TiO2(110)." The Journal of Physical Chemistry Letters 1, no. 17:2508-2513. PNNL-SA-73722. doi:10.1021/jz100884w
  • Petrik N.G., and G.A. Kimmel. 2010. "Photoinduced Dissociation of O2 on Rutile TiO2(110)." The Journal of Physical Chemistry Letters 1, no. 12:1758-1762. PNNL-SA-72411. doi:10.1021/jz100513e

2009

  • Akin M.C., N.G. Petrik, and G.A. Kimmel. 2009. "Electron-Stimulated Reactions and O-2 Production in Methanol-Covered Amorphous Solid Water Films." Journal of Chemical Physics 130, no. 10:Art. No. 104710. PNNL-SA-62554.
  • Petrik N.G., and G.A. Kimmel. 2009. "Nonthermal Water Splitting on Rutile TiO2: Electron-Stimulated Production of H-2 and O-2 in Amorphous Solid Water Films on TiO2(110)." Journal of Physical Chemistry C 113, no. 11:4451-4460. PNNL-SA-60869.
  • Petrik N.G., Z. Zhang, Y. Du, Z. Dohnalek, I. Lyubinetsky, and G.A. Kimmel. 2009. "Chemical Reactivity of Reduced TiO2(110): The dominant role of surface defects in oxygen chemisorption." Journal of Physical Chemistry C 113, no. 28:12407-12411. PNNL-SA-65119. doi:10.1021/jp901989x
  • Zhang Z., Y. Du, N.G. Petrik, G.A. Kimmel, I. Lyubinetsky, and Z. Dohnalek. 2009. "Water as a Catalyst: Imaging Reactions of O-2 with Partially and Fully Hydroxylated TiO2(110) Surfaces." Journal of Physical Chemistry C 113, no. 5:1908-1916. PNNL-SA-62836.

2008

  • Grieves G.A., N.G. Petrik, J. Herring-Captain, B. Olanrewaju, A. Aleksandrov, R.G. Tonkyn, and S.E. Barlow, et al. 2008. "Photoionization of Sodium Salt Solutions in a Liquid Jet." Journal of Physical Chemistry C 112, no. 22:8359-8364. PNNL-SA-58466. doi:10.1021/jp7102534
  • Kimmel G.A., and N.G. Petrik. 2008. "Tetraoxygen on Reduced Ti02(110): Oxygen Adsorption and Reactions with Oxygen Vacancies." Physical Review Letters 100, no. 19:Art. No. 196102. PNNL-SA-58431. doi:10.1103/PhysRevLett.100.196102

2007

  • Kimmel G.A., N.G. Petrik, Z. Dohnalek, and B.D. Kay. 2007. "Crystalline Ice Growth on Pt(111) and Pd(111): Nonwetting Growth on a Hydrophobic Water Monolayer." Journal of Chemical Physics 126, no. 11:Art. No. 114702. PNNL-SA-51889.
  • Lane C.D., N.G. Petrik, T.M. Orlando, and G.A. Kimmel. 2007. "Electron-Stimulated Oxidation of Thin Water Films Adsorbed on TiO2(110)." Journal of Physical Chemistry C 111, no. 44:16319-16329. PNNL-SA-54544. doi:10.1021/jp072479o
  • Lane C.D., N.G. Petrik, T.M. Orlando, and G.A. Kimmel. 2007. "Site-Dependent Electron-Stimulated Reactions in Water Films on TiO2(110)." Journal of Chemical Physics 127, no. 22:Art. No. 224706. PNNL-SA-56026.
  • Petrik N.G., and G.A. Kimmel. 2007. "Hydrogen Bonding, H-D Exchange, and Molecular Mobility in Thin Water Films on TiO2(110)." Physical Review Letters 99, no. 19:Art.No.196103. PNNL-SA-55179. doi:10.1103/PhysRevLett.99.196103

2006

  • Kimmel G.A., N.G. Petrik, Z. Dohnalek, and B.D. Kay. 2006. "Layer-by-Layer Growth of Thin Amorphous Solid Water Films on Pt(111) and Pd(111)." Journal of Chemical Physics 125, no. 4:044713-1 - 044713-12. PNNL-SA-48867. doi:10.1063/1.2218844
  • Petrik N.G., A.G. Kavetski, and G.A. Kimmel. 2006. "Electron-Stimulated Production of Molecular Oxygen in Amorphous Solid Water on Pt(111): Precursor Transport Through the Hydrogen Bonding Network." Journal of Chemical Physics 125, no. 12:124702 (11 p.). PNNL-SA-50526.
  • Petrik N.G., A.G. Kavetski, and G.A. Kimmel. 2006. "Electron-Stimulated Production of Molecular Oxygen in Amorphous Solid Water." Journal of Physical Chemistry B 110, no. 6:2723-2731. PNNL-SA-46633.

2005

  • Garrett B.C., D.A. Dixon, D.M. Camaioni, D.M. Chipman, M.A. Johnson, C.D. Jonah, and G.A. Kimmel, et al. 2005. "Role of Water in Electron-Initiated Processes and Radical Chemistry: Issues and Scientific Advances." Chemical Reviews 105, no. 1:355-389. PNNL-SA-42304. doi:10.1021/cr030453x
  • Kimmel G.A., N.G. Petrik, Z. Dohnalek, and B.D. Kay. 2005. "Crystalline Ice Growth on Pt(111): Observation of a Hydrophobic Water Monolayer." Physical Review Letters 95, no. 16:166102. PNNL-SA-45342.
  • Lynch D.J., W.E. Wilson, M.T. Batdorf, M.B. Resat, G.A. Kimmel, and J.H. Miller. 2005. "Monte Carlo Simulation of the Spatial Distribution of Energy Deposition for an Electron Microbeam." Radiation Research 163, no. 4:468-472. PNNL-SA-44733.
  • Petrik N.G., and G.A. Kimmel. 2005. "Electron-Stimulated Sputtering of Thin Amorphous Solid Water Films on Pt(111)." Journal of Chemical Physics 123, no. 5:054702 (1-7). PNNL-SA-42923.
  • Petrik N.G., and G.A. Kimmel. 2005. "Low-Energy Electron-Stimulated Luminescence of Thin H20 and D20 Layers on Pt(111)." Journal of Physical Chemistry B 109, no. 33:15835-15841. PNNL-SA-43848.
  • Sowa M.B., L.E. Kathmann, B.A. Holben, B.D. Thrall, and G.A. Kimmel. 2005. "Low-LET Microbeam Investigation of the Track-End Dependence of Electron-Induced Damage in Normal Human Diploid Fibroblasts." Radiation Research 164, no. 5:677-679. PNNL-SA-42273.
  • Sowa M.B., M.K. Murphy, J.H. Miller, J.C. McDonald, D.J. Strom, and G.A. Kimmel. 2005. "A Variable-Energy Electron Microbeam: A Unique Modality for Targeted Low-LET Radiation." Radiation Research 164, no. 5:695-700. PNNL-SA-40439.

2004

  • Petrik N.G., and G.A. Kimmel. 2004. "Electron-Stimulated Production of Molecular Hydrogen at the Interfaces of Amorphous Solid Water Films on Pt(111)." Journal of Chemical Physics 121, no. 8:3736-3744. PNNL-SA-41294.
  • Petrik N.G., and G.A. Kimmel. 2004. "Electron-Stimulated Reactions in Thin D2O Films on Pt(111) Mediated by Electron Trapping." Journal of Chemical Physics 121, no. 8:3727-3735. PNNL-SA-41765.

2003

  • Kimmel G.A., M. Persson, Z. Dohnalek, and B.D. Kay. 2003. "Temperature Independent Physisorption Kinetics and Adsorbate Layer Compression for Ar Adsorbed on Pt (111)." Journal of Chemical Physics 119, no. 13:6776-6783. PNNL-SA-37480.
  • Petrik N.G., and G.A. Kimmel. 2003. ""Electron-Simulated Reactions at the Interfaces of Amorphous Solid Water Films Driven by Long-Range Energy Transfer from the Bulk"." Physical Review Letters 90, no. 16:166102. PNNL-SA-37444.

2002

  • Sowa M.B., G.A. Kimmel, J.H. Miller, J.C. Mcdonald, M.K. Murphy, D.J. Strom, and B.D. Thrall, et al. 2002. "Spatially Resolved Single-Cell Irradiator to Study Bystander Responses to Low-LET Radiation." Radiation Research 158, no. 3:375-376. PNNL-SA-40190.

1999

  • Orlando T.M., G.A. Kimmel, and W.C. Simpson. 1999. "Quantum-Resolved Electron Stimulated Interface Reactions: D2 Formation from D2O Films." Nuclear Instruments and Methods in Physics Research. Section B, Beam Interactions with Materials and Atoms 157. PNNL-SA-31500.

1997

  • Kimmel G.A., T.M. Orlando, P. Cloutier, and L. Sanche. 1997. "Low-Energy (5-40 eV) Electron-Stimulated Desorption of Atomic Hydrogen and Metastable Emission from Amorphous Ice." Journal of Physical Chemistry B 101, no. 32:6301-6303. PNNL-SA-28046. doi:10.1021/jp9632091
  • Orlando T.M., and G.A. Kimmel. 1997. "The Role of Excitons and Substrate Temperature in Low-Energy (5-50 eV) Electron-Stimulated Dissociation of Amorphous D2O Ice." Surface Science 390, no. 1-3:79-85. PNNL-SA-28659. doi:10.1016/S0039-6028(97)00511-6

1996

  • Kimmel G.A., and T.M. Orlando. 1996. "Observation of Negative Ion Resonances in Amorphous Ice via Low-Energy (5-40 eV) Electron-Stimulated Production of Molecular Hydrogen." Physical Review Letters 77, no. 19:3983-3986. PNNL-SA-27600. doi:10.1103/PhysRevLett.77.3983

1995

  • Kimmel G.A., and T.M. Orlando. 1995. "Low-Energy (5-120 eV) Electron-Stimulated Dissociation of Amorphous D2O Ice: D(2S), O(3P2,1,0), and O(1D2) Yields and Velocity Distributions." Physical Review Letters 75, no. 13:2606-2609. PNL-SA-26352. doi:10.1103/PhysRevLett.75.2606

1994

  • Kimmel G.A., T.M. Orlando, C. Vezina, and L. Sanche. 1994. "Low-Energy Electron-Stimulated Production of Molecular Hydrogen from Amorphous Water Ice." Journal of Chemical Physics 101, no. 4:3282-3286. PNL-SA-23672. doi:10.1063/1.468430

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