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Ahren W. Jasper

Theoretical Chemist

Biography

  • Theoretical Chemist, Argonne National Laboratory, 2016–present
  • Principal Member of the Technical Staff, Combustion Research Facility, Sandia National Laboratories, 20072016
  • Postdoctoral Associate, Argonne National Laboratory, 20052007
  • Postdoctoral Associate, University of Minnesota, 20032005

Education

  • PhD, Physical Chemistry, University of Minnesota, 2003
  • BA, Chemistry, Gustavus Adolphus College, St. Peter, Minnesota, 1998

Research

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Gas Phase Chemical Dynamics Group

The outcome of a gas phase chemical reaction is the result of competition between a variety of underlying microscopic processes, including collisional energy transfer, internal energy redistribution, bonding rearrangements, and, sometimes, inherently quantum mechanical events like electronic transitions. These same phenomena govern reactivity in more complex energetic environments, and one of our main goals is to develop a comprehensive set of first-principles approaches for describing the fundamental chemical physics of these phenomena with high accuracy and that are broadly applicable throughout chemistry.

The improvement of first-principles theories via the construction of more and more detailed physical models benefits from the increasing impact of large-scale computing in chemistry, including Argonne’s own leadership-class resources. Our focus on the development of methods and codes for dynamics and kinetics recognizes that these approaches are now poised to take full advantage of the tremendous advances made in electronic structure theory over the past several decades.

We often pursue the development of semiclassical strategies, where the term is used here to describe approaches that incorporate one or more quantum effect into dynamics simulations involving classical or nearly classical nuclear motion. Semiclassical methods offer a scalable balance of computational cost and accuracy and are thus well suited for high performance computing. We focus on the advancement of first-principles semiclassical approaches, i.e., methods that are systematically improvable, and we have demonstrated in a variety of contexts that our most detailed models have accuracies that match and sometimes even exceed what is possible experimentally.

The increased accuracy of a priori theory and its use alongside experiment as an independent source of quantitative chemical and physical information may be anticipated to have a transformative effect in chemical modeling.

Recent work has continued the development of methods and codes for nonadiabatic dynamics and intersystem crossing, collisional energy transfer and transport, potential energy surface fitting, nonequilibrium reactivity, and rovibrational anharmonicity at high energies and temperatures.

Publications

Isomer-selective detection of keto-hydroperoxides in the low-temperature oxidation of tetrahydrofuran
N. Hansen, K. Moshammer, and A. W. Jasper J. Phys. Chem. A, in press (2019). DOI

Anharmonic rovibrational partition functions at high temperatures: Tests of reduced-dimensional models for systems with up to three fluxional modes 
A. W. Jasper, L. B. Harding, C. Knight, and Y. Georgievskii, J. Phys. Chem. A, 123, 62106228 (2019). DOI

Large Intermediates in hydrazine decomposition: A theoretical study of the N3H5 and N4H6 potential energy surfaces 
A. Grinberg Dana, K. B. Moore, A. W. Jasper, and W. H. Green, J. Phys. Chem. A, 123, 46794692 (2019). DOI

Parameterization strategies for intermolecular potentials for predicting trajectory-based collision parameters 
A. W. Jasper and M. J. Davis, J. Phys. Chem. A 123, 34643480 (2019). DOI

Identification of the Criegee intermediate reaction network in ethylene ozonolysis: Impact on energy conversion strategies and atmospheric chemistry 
A. C. Rousso, N. Hansen, A. W. Jasper, and Y. Ju, Phys. Chem. Chem. Phys. 21, 73417357 (2019). DOI

Nonthermal rate constants for CH4* + X → CH3 + HX, X = H, O, OH, and O2 
A. W. Jasper, R. Sivaramakrishnan, and S. J. Klippenstein, J. Chem. Phys. 150, 114112 (2019). DOI

Automated computational thermochemistry for butane oxidation: A prelude to predictive automated combustion kinetics
M. Keçeli, S. Elliott, Y.-P. Li, M. S. Johnson, C. Cavallotti, Y. Georgievskii, W. H. Green M. Pelucchi, J. M. Wozkiak, A. W. Jasper, and S. J. Klippenstein, Proc. Combust. Inst. 37, 363371 (2019). DOI

Toward accurate high temperature anharmonic partition functions
D. H. Bross, A. W. Jasper, B. Ruscic, and A. F. Wagner, Proc. Combust. Inst. 37, 315322 (2019). DOI

Low-temperature oxidation of ethylene by ozone in a jet-stirred reactor
A. C. Rousso, N. Hansen, A. W. Jasper, and Y. Ju, J. Phys. Chem. A 12286748685 (2018). DOI

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, and S. J. Klippenstein, J. Chem. Phys. 148, 174306 (2018). DOI

Exploring the negative temperature coefficient behavior of acetaldehyde based on detailed intermediate measurements in a jet stirred reactor
T. Tao, W. Sun, N. Hansen, A. W. Jasper, K. Moshammer, B. Chen, Z. Wang, C. Huang, P. Dagaut, B. Yang, Combust. Flame 192, 120129 (2018). DOI

Anharmonic rovibrational partition functions for fluxional species at high temperatures via Monte Carlo phase space integrals
A. W. Jasper, Z. B. Gruey, L. B. Harding, Y. Georgievskii, S. J. Klippenstein, and A. F. Wagner, J. Phys. Chem. A 122, 12721740 (2018). DOI

Theory and modeling of relevance to prompt-NO formation at high pressure
S. J. Klippenstein, M. Pfeifle, A. W. Jasper, and P. Glarborg, Combust. Flame 195, 317 (2018). DOI

Theoretical investigation of intersystem crossing in the cyanonitrene molecule, 1NCN3NCN
M. Pfeifle, Y. Georgievskii, A. W. Jasper, and S. J. Klippenstein, J. Chem. Phys. 147, 084310 (2017). DOI

Theoretical study of the Ti-Cl bond cleavage reaction in TiCl4
D. Nurkowski, A. W. Jasper, J. Akroyd, and M. Kraft, Z. Phys. Chem. 231, 14891506 (2017). DOI

Temperature- and pressure-dependent rate coefficients for the HACA pathways from benzene to naphthalene
A. M. Mebel, Y. Georgievskii, A. W. Jasper, and S. J. Klippenstein, Proc. Combust. Inst. 36, 919926 (2017). DOI

Theoretical kinetics of O + C2H4
X. Li, A. W. Jasper, J. Zádor, J. A. Miller, and S. J. Klippenstein, Proc. Combust. Inst. 36, 219227 (2017). DOI

Recombination and dissociation of 2-methyl allyl radicals: Experiment and theory
R. S. Tranter, A. W. Jasper, J. B. Randazzo, J. P. A. Lockhart, and J. P. Porterfield, Proc. Combust. Inst. 36, 211218 (2017). DOI

Pressure dependent rate constants for PAH growth: Formation of indene and its conversion to naphthalene
A. M. Mebel, Y. Georgievskii, A. W. Jasper, and S. J. Klippenstein, Faraday Discuss. Chem. Soc. 195, 637 (2016). DOI

Low temperature kinetics of the first steps of water cluster formation
J. Bourgalais, V. Roussel, M. Capron, A. Benidar, A. W. Jasper, S. J. Klippenstein, L. Beinnier, and S. D. Le Picard, Phys. Rev. Lett. 115, 113401 (2016). DOI

Comment on When rate constants are not enough”
J. A. Miller, S. J. Klippenstein, S. H. Robertson, M. J. Pilling, R. Shannon, J. Zádor, A. W. Jasper, C. F. Goldsmith, and M. P. Burke, J. Phys. Chem. A 120, 306 (2016). DOI

Determination of the collisional energy transfer distribution responsible for the collision-induced dissociation of NO2 with Ar
J. D. Steill, A. W. Jasper, and D. W. Chandler, Chem. Phys. Lett. 636, 1 (2015). (Frontiers Article). DOI

Thermal dissociation and roaming isomerization of nitromethane: Experiment and theory
C. J. Annesley, J. B. Randazzo, S. J. Klippenstein, L. B. Harding, A. W. Jasper, Y. Georgievski, R. S. Tranter, J. Phys. Chem. A 119, 7872 (2015). (Harding, Michael, Wagner ANL Festschrift). DOI

Kinetics of propargyl radical dissociation
S. J. Klippenstein, J. A. Miller, and A. W. Jasper, J. Phys. Chem. A 119, 7780 (2015). (Harding, Michael, Wagner ANL Festschrift). DOI

Detection and identification of the keto-hydroperoxide (HOOCH2OCHO) and other intermediates during low-temperature oxidation of dimethyl ether
K. Moshammer, A. W. Jasper, S. M. Popolan-Vaida, A. Lucassen, P. Dievart, H. Selim, A. J. Eskola, C. A. Taatjes, S. R. Leone, S. M. Sarathy, Y. Ju, P. Dagaut, K. Kohse-Hoinghaus, and N. Hansen, J. Phys. Chem. A 119, 7361 (2015). (Harding, Michael, Wagner ANL Festschrift). DOI

Multidimensional effects in nonadiabatic statistical theories of spin-forbidden kinetics: A case study of 3O + CO CO2
A. W. Jasper, J. Phys. Chem. A 119, 7339 (2015). (Harding, Michael, Wagner ANL Festschrift) DOI

Ab initio variational transition state theory and master equation study of the reaction (OH)3SiOCH2 + CH3 → (OH)3SiOC2H5
D. Nurkowski, S. J. Klippenstein, Y. Georgievskii, M. Verdicchio, A. W. Jasper, J. Akroyd, S. Mosabach, M. Kraft, Z. Phys. Chem. 229, 691 (2015). DOI

Third-body” collision efficiencies for combustion modeling: Hydrocarbons in atomic and diatomic baths
A. W. Jasper, C. M. Oana, and J. A. Miller, Proc. Combust. Inst. 35, 197 (2015). DOI

Predictive a priori pressure dependent kinetics
A. W. Jasper, K. M. Pelzer, J. A. Miller, E. Kamarchik, L. B. Harding, and S. J. Klippenstein, Science 346, 1212 (2014). DOI

First-principles binary diffusion coefficients for H, H2, and four normal alkanes + N2
A. W. Jasper, E. Kamarchik, J. A. Miller, and S. J. Klippenstein, J. Chem. Phys. 141, 124313 (2014). DOI

Lennard-Jones parameters for combustion and chemical kinetics modeling from full-dimensional intermolecular potentials
A. W. Jasper and J. A. Miller, Combust. Flame 161, 101 (2014). DOI

The collision efficiency of water in the unimolecular reaction CH4 (+ H2O) CH3 + H (+ H2O): One-dimensional and two-dimensional solutions of the low-pressure-limit master equation
A. W. Jasper, J. A. Miller, and S. J. Klippenstein, J. Phys. Chem. A 117, 12243 (2013). DOI

Non-Born–Oppenheimer molecular dynamics of the spin-forbidden reaction O(3P) + CO(X 1Σ+) ~> CO2(X 1Σg+)
A. W. Jasper and R. Dawes, J. Chem. Phys. 139, 154313 (2013). DOI

Anharmonic vibrational properties from intrinsic n-mode state densities
E. Kamarchik and A. W. Jasper, J. Phys. Chem. Lett. 4, 2430 (2013). DOI

Anharmonic state counts and partition functions for molecules via classical phase space integrals in curvilinear coordinates
E. Kamarchik and A. W. Jasper, J. Chem. Phys. 138, 194109 (2013). DOI

Hydrogen-assisted isomerizations of fulvene to benzene and of larger cyclic aromatic hydrocarbons
A. W. Jasper and N. Hansen, Proc. Combust. Inst. 34, 279 (2013). DOI

Separability of tight and roaming pathways to molecular decomposition
L. B. Harding, S. J. Klippenstein, and A. W. Jasper, J. Phys. Chem. A 116, 6967 (2012). DOI

Chemical structures of low-pressure premixed methylcyclohexane flames as benchmarks for the development of a predictive combustion chemistry model
S. A. Skeen, B. Yang, A. W. Jasper, W. J. Pitz, and N. Hansen, Energy & Fuels 25, 5611 (2011). DOI

Identification of tetrahydrofuran reaction pathways in premixed flames
T. Kasper, A. Lucassen, A. W. Jasper, W. Li, B. Yang, P. R. Westmoreland, K. Kohse-Höinghaus, J. Wang, T. A. Cool, and N. Hansen, Z. Phys. Chem. 225, 1237 (2011). (Kohse-Höinghaus Festschrift). DOI

Theoretical unimolecular kinetics for CH4 + M CH3 + H + M in eight baths, M = He, Né, Ar, Kr, H2, CO, N2, and CH4
A. W. Jasper and J. A. Miller, J. Phys. Chem. A 115, 6438 (2011). DOI

The vibration–rotation–tunneling spectrum of the polar and T-shaped-N-in isomers of (NNO)2
X.-G. Wang, T. Carrington Jr., R. Dawes, and A. W. Jasper, J. Mol. Spectrosc. 268, 53 (2011). DOI

Roaming radicals in the thermal decomposition of dimethyl ether: Experiment and theory
R. Sivaramakrishnan, J. V. Michael, A. F. Wagner, R. Dawes, A. W. Jasper, L. B. Harding, Y. Georgievskii, and S. J. Klippenstein, Combust. Flame 158, 618 (2011). DOI

A shock tube and theoretical study on the pyrolysis of 1,4-dioxane
X. Yang, A. W. Jasper, B. R. Giri, J. H. Kiefer, and R. S. Tranter, Phys. Chem. Chem. Phys. 13, 3686 (2011). DOI

Non-Born–Oppenheimer molecular dynamics for conical intersections, avoided crossings, and weak interactions
A. W. Jasper and D. G. Truhlar, in Conical Intersections: Theory, Computation, and Experiment, edited by W. Domcke, D. R. Yarkony, and H. Koppel (World Scientific, Singapore, 2011), pp. 375412DOI

Global potential energy surface, vibrational spectrum, and reaction dynamics of the first excited (A 2A’) state of HO2
A. Li, D. Xie, R. Dawes, A. W. Jasper, J. Ma, and H. Guo, J. Chem. Phys. 133, 144306 (2010). DOI

Nitrous oxide dimer: A new potential energy surface and rovibrational spectrum of the nonpolar isomer
R. Dawes, X.-G. Wang, A. W. Jasper, and T. Carrington, Jr., J. Chem. Phys. 133, 134304 (2010). DOI

The role of excited electronic states in hypervelocity collisions: Enhancement of the O(3P)+HCl → OCl+H reaction channel
A. J. Binder, R.  Dawes, A. W. Jasper, and J. P. Camden, J. Phys. Chem. Lett. 1, 2940 (2010). DOI

The effect of spin-orbit splitting on the association kinetics of barrierless halogen atom–hydrocarbon radical reactions
A. W. Jasper, S. J. Klippenstein, and L. B. Harding, J. Phys. Chem. A 114, 5759 (2010). DOI

Theoretical and experimental spectroscopy of the S2 state of CHF and CDF: Dynamically weighted multireference configuration interaction calculations for high-lying electronic states
R. Dawes, A. W. Jasper, C. Tao, C. Richmond, C. Mukarakate, S. H. Kable, and S. A. Reid, J. Phys. Chem. Lett. 1, 641 (2010). DOI

The reaction between propene and hydroxyl
J. Zádor, A. W. Jasper, and J. A. Miller, Phys. Chem. Chem. Phys. 11, 11040 (2009). DOI

The dissociation of diacetyl: A shock tube and theoretical study
X. Yang, A. W. Jasper, J. H. Kiefer, and R. S. Tranter, J. Phys. Chem. A 113, 8318 (2009). DOI

Coupled-surface investigation of the photodissociation of NH3(Ã): Effect of exciting the symmetric and antisymmetric stretching modes
D. Bomhommeau, R. Valero, D. G. Truhlar, and A. W. Jasper, J. Chem. Phys. 130, 234303 (2009). DOI

Collisional energy transfer in unimolecular reactions: Direct classical trajectories for CH4CH3 + H in Helium
A. W. Jasper and J. A. Miller, J. Phys. Chem. A 113, 561 (2009). DOI

Theoretical rate coefficients for the reaction of methyl radical with hydroperoxyl radical and for methylhydroperoxide decomposition
A. W. Jasper, S. J. Klippenstein, and L. B. Harding, Proc. Combust. Inst. 32, 279 (2008). DOI

Photodissociation of HBr: Semiclassical trajectory study using adiabatic states derived from a spin-coupled diabatic transformation
R. Valero, D. G. Truhlar, A. W. Jasper, J. Phys. Chem. A 112, 5756 (2008). DOI

The thermal decomposition of CF3 and the reaction of CF2 + OH CF2O + H
N. K. Srinivasan, M.-C. Su, J. V. Michael, A. W. Jasper, S. J. Klippensein, and L. B. Harding, J. Chem. Phys. A 112, 31 (2008). DOI

Al nanoparticles: Accurate potential energy functions and physical properties
N. E. Schultz, A. W. Jasper, D. Bhatt, J. I. Siepmann, and D. G. Truhlar, in Multiscale Simulation Methods for Materials, edited by R. B. Ross and S. Mohanty (Wiley, 2008), pp. 169188.

Structures, rugged energetic landscapes, and nanothermodynamics of Aln (2n65) particles
Z. H. Li, A. W. Jasper, and D. G. Truhlar, J. Am. Chem. Soc. 129, 14899 (2007). DOI

Non-Born–Oppenheimer molecular dynamics study of the photodissociation of Na…FH
A. W. Jasper and D. G. Truhlar, J. Chem. Phys. 127, 194306 (2007). DOI

Secondary kinetics of methanol decomposition
A. W. Jasper, S. J. Klippenstein, and L. B. Harding, J. Phys. Chem. A 111, 8699 (2007). DOI

Ab initio methods for reactive potential energy surfaces
L. B. Harding, S. J. Klippenstein, and A. W. Jasper, Phys. Chem. Chem. Phys. 9, 4055 (2007). DOI

Kinetics of the reaction of methyl radical with hydroxyl radical and methanol decomposition
A. W. Jasper, S. J. Klippenstein, L. B. Harding, and B. Ruscic, J. Phys. Chem. A 111, 3932 (2007). (James A. Miller Festschrift). DOI

Transferability of orthogonal and nonorthogonal tight binding models for aluminum clusters and nanoparticles
A. W. Jasper, N. E. Schultz, and D. G. Truhlar, J. Chem. Theory Comput. 3, 210 (2007). DOI

Phase behavior of elemental aluminum using Monte Carlo simulations
D. Bhatt, N. E. Schultz, A. W. Jasper, J. I. Siepmann, and D. G. Truhlar, J. Phys. Chem. B 110, 26135 (2006). DOI

Critical properties of aluminum
D. Bhatt, A. W. Jasper, N. E. Schultz, J. I. Siepmann, and D. G. Truhlar, J. Am. Chem. Soc. 128, 4225 (2006). DOI

Non-Born–Oppenheimer molecular dynamics
A. W. Jasper, S. Nangia, C. Zhu, and D. G. Truhlar, Acc. Chem. Res. 39, 99 (2006). DOI

Electronic decoherence time for non-Born–Oppenheimer trajectories
A. W. Jasper and D. G. Truhlar, J. Chem. Phys. 123, 064103 (2005). DOI

Non-Born–Oppenheimer Liouville–von Neumann dynamics. Evolution of a subsystem controlled by linear and population-driven decay of mixing with decoherent and coherent switching
C. Zhu, A. W. Jasper, and D. G. Truhlar, J. Chem. Theory Comput. 1, 572 (2005). DOI

Analytic potential energy functions for simulating aluminum nanoparticles
A. W. Jasper, N. E. Schultz, and D. G. Truhlar, J. Phys. Chem. B 109, 3915 (2005). DOI

Conical intersections and semiclassical trajectories:  Comparison to accurate quantum dynamics and analyses of the trajectories
A. W. Jasper and D. G. Truhlar, J. Chem. Phys. 122, 044101 (2005). DOI

Coherent switching with decay of mixing: An improved treatment of electronic coherence for non-Born–Oppenheimer trajectories
C. Zhu, S. Nangia, A. W. Jasper, and D. G. Truhlar, J. Chem. Phys. 121, 7658 (2004). DOI

Introductory lecture: Nonadiabatic effects in chemical dynamics
A. W. Jasper, C. Zhu, S. Nangia, and D. G. Truhlar, Faraday Discuss. 127, 1 (2004). DOI

Analytic potential energy functions for aluminum clusters
A. W. Jasper, P. Staszewski, G. Staszewska, N. E. Schultz, and D. G. Truhlar, J. Phys. Chem. B 108, 7658 (2004). DOI

Non-Born–Oppenheimer trajectories with self-consistent decay of mixing
C. Zhu, A. W. Jasper, and D. G. Truhlar, J. Chem. Phys. 120, 5543 (2004). DOI

Army ants algorithm for rare event sampling of delocalized nonadiabatic transitions by trajectory surface hopping and the estimation of sampling errors by the bootstrap method
S. Nangia, A. W. Jasper, T. F. Miller III, and D. G. Truhlar, J. Chem. Phys. 120, 3586 (2004). DOI

Non-Born–Oppenheimer chemistry: Potential surfaces, couplings, and dynamics
A. W. Jasper, B. K. Kendrick, C. A. Mead, and D. G. Truhlar, in Modern Trends in Chemical Reaction Dynamics, Part I, edited by X. Yang and K. Liu (World Scientific, Singapore, 2004), pp. 329392DOI

Narrow subthreshold quantum mechanical resonances in the Li + HF → H + LiF reaction
L. Wei, A. W. Jasper, and D. G. Truhlar, J. Phys. Chem. A 107, 7236 (2003). DOI

Improved treatment of momentum at classically forbidden electronic transitions in trajectory surface hopping calculations
A. W. Jasper and D. G. Truhlar, Chem. Phys. Lett. 369, 60 (2003). DOI

Coupled quasidiabatic potential energy surfaces for LiFH
A. W. Jasper, M. D. Hack, D. G. Truhlar, and P. Piecuch, J. Chem. Phys. 116, 8353 (2002). DOI

Fewest-switches with time uncertainty: A modified trajectory surface-hopping algorithm with better accuracy for classically forbidden electronic transitions
A. W. Jasper, S. N. Stechmann, and D. G. Truhlar, J. Chem. Phys. 116, 5424 (2002); 117, 10427(E) (2002). DOI

Photodissociation of LiFH and NaFH van der Waals complexes:  A semiclassical trajectory study
A. W. Jasper, M. D. Hack, A. Chakraborty, D. G. Truhlar, and P. Piecuch, J. Chem. Phys. 115, 7945 (2001); 119, 9321(E) (2003). DOI

The treatment of classically forbidden electronic transitions in semiclassical trajectory surface hopping calculations
A. W. Jasper, M. D. Hack, and D. G. Truhlar, J. Chem. Phys. 115, 1804 (2001). DOI

Do semiclassical trajectory theories provide an accurate picture of radiationless decay for systems with accessible surface crossings?
M. D. Hack, A. W. Jasper, Y. L. Volobuev, D. W. Schwenke, and D. G. Truhlar, J. Phys. Chem. A 104, 217 (2000). DOI

Quantum mechanical and quasiclassical trajectory surface hopping studies of the electronically nonadiabatic predissociation of the à state of NaH2
M. D. Hack, A. W. Jasper, Y. L. Volobuev, D. W. Schwenke, and D. G. Truhlar, J. Phys. Chem. A 103, 6309 (1999). DOI