• B.Sc. (1983) Mathematics and Chemistry (Honours), University of British Columbia, Canada
• Ph.D. (1988) Physical Chemistry, California Institute of Technology
  • Thesis Title: Theoretical Studies of Chemical Reaction Dynamics   
  • Advisor: Prof. R. A. Marcus
• Postdoc (1988) with Rudy Marcus, California Institute of Technology                    
• Postdoc (1988,1989) with Casey Hynes, University of Colorado, Boulder              
• Assistant, Associate, Full Professor (1989-2000) Department of Chemistry, Case Western Reserve University                 
• Principal Member of the Technical Staff (2000-2005) Combustion Research Facility, Sandia National Laboratories, Livermore    
• Senior Chemist (2005-2013) Chemical Sciences and Engineering, Argonne  
• Distinguished Fellow (2013-) Chemical Sciences and Engineering, Argonne  

 

Research Interests: Developing theoretical methods for predicting the kinetics and dynamics of gas phase reactions and applying them to interesting problems in combustion, interstellar, and atmospheric chemistry. Our studies typically involve some combination of electronic structure calculations, transition state theory, trajectory simulations, and master equation modeling. One focus of our work involves exploring and improving the accuracy of such calculations. Another focus involves the use of such methods to understand novel experimental observations and to improve global models for the chemistry of complex environments. Recently, we have begun automating our computational procedures in order to utilize leadership class computing facilities for the in silico development of global chemical models.

Recent Publications

Automated Theoretical Chemical Kinetics: Exploring the Initial Stages of Pyrolysis, S. N. Elliott, K. B. Moore III, A. V. Copan, M. Keceli, C. Cavallotti, Y. Georgievskii, H. F. Schaefer III, S. J. Klippenstein, Proc. Combust. Inst., in press (2020).

 

Termolecular Chemistry Facilitated by Radical-Radical Recombinations and its Impact on Flame Speed Predictions, Y. Tao, A. W. Jasper, Y. Georgievskii, S. J. Klippenstein, R. Sivaramakrishnan, Proc. Combust. Inst., in press (2020).

 

Low Temperature Oxidation of Diethyl Ether: Reactions of Hot Radicals Across Coupled Potential Energy Surfaces, A. D. Danilack, S. J. Klippenstein, C. F. Goldsmith, Proc. Combust. Inst., in press (2020).

Direct Kinetic Measurements and Theoretical Predictions of an Isoprene-Derived Criegee Intermediate R. L. Caravan, M. F. Vansco, K. Au, M. A. H. Khan, Y.-L. Li, F. A. F. Winiberg, K. L. Zuraski, Y.-H. Lin, W. Chao, N. Trongsiriwat, P. J. Walsh, D. L. Osborn, C. J. Percival, J. Jr-M. Lin, D. E. Shallcross, L. Sheps, S. J. Klippenstein, C. A. Taatjes,  M. I. Lester, Proc. Nat. Acad. Sci. 117, 9733-9740 (2020).

Experimental and Theoretical Studies of the Doubly-Substituted Methyl-Ethyl Criegee Intermediate: Infrared Action Spectroscopy and Unimolecuar Decay to OH Radical Product, V. P. Barber, A. S. Hansen, S. J. Klippenstein, M. I. Lester, J. Chem. Phys. 152, 094301 (2020).

 

 

Reaction Profiles and Kinetics for Radical-Radical Hydrogen Abstraction via Multireference Coupled Cluster Theory, Chia-Hua Wu, D. Brandon Magers, Lawrence B. Harding, Stephen J. Klippenstein, and Wesley D. Allen, J. Chem. Theory Comp. 16, 1511-1525 (2020).

Photodissociation Transition States Characterized by Chirped Pulse Millimeter Wave Spectroscopy, K. Prozument, J. H. Baraban, P. B. Changala, G. B. Park, R. G. Shaver, J. S. Muenter, S. J. Klippenstein, V. Y. Chernyak, R. W. Field, Proc. Nat. Acad. Sci. 117, 146-151 (2020).

Synthesis, Electronic Spectroscopy, and Photochemistry of Methacrolein Oxide: A Four-Carbon Unsaturated Criegee Intermediate from Isoprene Ozonolysis, M. F. Vansco, B. Marchetti, N. Tronsiriwat, T. Bhagde, G. Wang, P. J. Walsh, S. J. Klippenstein, M. I. Lester, J. Am. Chem. Soc. 141, 15058-15069 (2019).

 

 

Propane Clusters in Titan’s Lower Atmosphere: Insights from a Combined Theory/Laboratory Study, J. Bourgalais, O. Durif, S. D. Le Picard, P. Lavvas, F. Calvo, S. J. Klippenstein, L. Biennier, Mon. Not. Roy. Ast. Soc. 488, 676-684 (2019).

 

 

Ab Initio Kinetics for Pyrolysis and Combustion Systems, S. J. Klippenstein,  C. Cavallotti, Chapter in: Mathematical Modeling of Complex Reaction Systems: Pyrolysis and Combustion, T. Faravelli, F. Manenti, and E. M. Ranzi, Eds. Computer Aided Chemical Engineering Series, 115-169 (2019).

 

 

Nonthermal Rate Constants for CH₄* + X -> CH₃ + HX, X = H, O, OH, and O_2,A. W. Jasper, R. Sivaramakrishnan, S. J. Klippenstein, J. Chem. Phys. 150, 114112 (2019).

 

EStokTP: Electronic Structure to Temperature and Pressure Dependent Rate Constants; A Code for Automatically Predicting the Thermal Kinetics of Reactions, C. Cavallotti, M. Pelucchi, Y. Georgievskii, S. J. Klippenstein, J. Chem. Theor. Comp. 15, 1122-1145 (2019).

Automated Computational Thermochemistry for Butane Oxidation: A Prelude to Predictive Automated Combustion Kinetics, ​​​​​M. Keceli, S. N. Elliott, Y.-P. Li, M. S. Johnson, C. Cavallotti, Y. Georgievskii, W. H. Green, M. Pelucchi, J. M. Wozniak, A. W. Jasper, S. J. Klippenstein, Proc. Combust. Inst. 37, 363-371 (2019).

 

 

 

Kinetics of 1-Butyl and 2-Butyl Radical Reactions with Molecular Oxygen: Experiment and Theory, A. J. Eskola, T. T. Pekkanen, S. P. Joshi, R. S. Timonen, S. J. Klippenstein, Proc. Combust. Inst., 37, 291-298 (2019).

 

 

 

Theory and Modeling of Relevance to Prompt-NO Formation at High Pressure, S. J. Klippenstein, M. Pfeifle, A. W. Jasper, P. Glarborg, Combust. Flame, 195, 3-17 (2018).

 

 

 

 

Nascent Energy Distribution of the Criegee Intermediate CH₂OO from Direct Dynamics Calculations of Primary Ozonide Dissociation M. Pfeifle, Y.-T. Ma, A. W. Jasper, L. B. Harding, W. L. Hase,  S. J. Klippenstein, J. Chem. Phys., 148, 174306 (2018).

 

Simulating the Density of Organic Species in the Atmosphere of Titan with a Coupled Ion-Neutral Photochemical Model, V. Vuitton, R. V. Yelle, S. J. Klippenstein, P. Lavvas, and S. M. Horst, Icarus, 324, 120-197 (2019).

 

 

 

Modeling Nitrogen Chemistry in Combustion, Peter Glarborg, Branko Ruscic, James A. Miller, and Stephen J. Klippenstein, Prog. Energy Combust. Sci., 67, 31-68 (2018).

 

 

 

Four Carbon Criegee Intermediate from Isoprene Ozonolysis: Methyl Vinyl Ketone Oxide Synthesis, Infrared Spectrum, and OH Production, Victoria P. Barber, Shubhrangshu Pandit, Amy M. Green, Nisalak Trongsiriwat, Patrick J. Walsh, Stephen J. Klippenstein, Marsha I. Lester, J. Am. Chem. Soc., 140, 10866-10880 (2018).

Unimolecular Decay of Criegee Intermediates to OH Radical Products: Prompt and Thermal Decay Processes, Marsha I. Lester, Stephen J. Klippenstein, Acc. Chem. Res., 51, 978-985 (2018).

 

Automated Computational Thermochemistry for Butane Oxidation: A Prelude to Predictive Automated Combustion Kinetics, Murat Keceli, Sarah N. Elliott, Yi-Pei Li, Matthew S. Johnson, Carlo Cavallotti, Yuri Georgievskii, William H. Green, Matteo Pelucchi, Justin M. Wozniak, Ahren W. Jasper, Stephen J. Klippenstein, Proc. Combust. Inst., 37, 367-371 (2018).

 

Ephemeral Collision Complexes Mediate Chemically Termolecular Transformations that Affect System Chemistry, Michael P. Burke and Stephen J. Klippenstein, Nature Chem., 9, 1078-1082 (2017).

 

 

Ab Initio Computations and Active Thermochemical Tables Hand in Hand: Heats of Formation of Core Combustion Species, Stephen J. Klippenstein, Lawrence B. Harding, and Branko Ruscic, J. Phys. Chem. A, 121, 6580-6602 (2017).

 

Dynamic Time-Resolved Chirped-Pulse Rotational Spectroscopy of Vinyl Cyanide Photoproducts in a Room Temperature Flow Reactor, Daniel P. Zaleski, Lawrence B. Harding, Stephen J. Klippenstein, Branko Ruscic, and Kirill Prozument, J. Phys. Chem. Lett., 8, 6180-6188 (2017).

 

 

Temperature- and Pressure-Dependent Rate Coefficients for the HACA Pathways from Benzene to Naphthalene, Alexander M. Mebel, Yuri Georgievskii, Ahren W. Jasper, and Stephen J. Klippenstein, Proc. Combust. Inst. 36, 919-926 (2017).

 

 

 

From Theoretical Reaction Dynamics to Chemical Modeling of Combustion, Stephen J. Klippenstein , Proc. Combust. Inst., 36, 77-111 (2017).

 

 

 

 

Low Temperature Kinetics of the First Steps of Water Cluster Formation, Jeremy Bourgalais, Vivien Roussel, Michael Capron, Abdou Benidar, Ahren W. Jasper, Stephen J. Klippenstein, Ludovic Biennier, and Sebastien D. Le Picard, Phys. Rev. Lett., 116, 113401 (2016).

 

 

 

Weakly Bound Free Radicals In Combustion: ​“Prompt” Dissociation of Formyl Radicals and Its Effect on Laminar Flame Speeds, Nicole J. Labbe, Raghu Sivaramakrishnan, C. Franklin Goldsmith, Yuri Georgievskii, James A. Miller, and Stephen J. Klippenstein, J. Phys. Chem. Lett., 7, 85-89 (2016).

 

 

Understanding Low Temperature First Stage Ignition Delay: Propane, Shamel S. Merchant, C. Franklin Goldsmith, Michael P. Burke, Stephen J. Klippenstein, and William H. Green, Combust. Flame, 162, 3658-3673 (2015).

 

 

 

Predictive A Priori Pressure Dependent Kinetics, Ahren W. Jasper, Kenley M. Pelzer, James A. Miller, Eugene Kamarchik, Lawrence B. Harding, and Stephen J. Klippenstein, Science, 346 1212-1215 (2014).