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Shawn Kathmann

Chemical Physics & Analysis
Pacific Northwest National Laboratory
PO Box 999
MSIN: K1-83
Richland, WA 99352


Dr. Shawn M. Kathmann joined the Environmental Molecular Sciences Laboratory of PNNL in February of 2000. He is staff member of the Chemical Physics and Analysis Group in the Physical and Computational Sciences Directorate since that time and is currently a senior research scientist.

Dr. Kathmann is interested in the development of chemical physics and statistical mechanical methods describing the kinetics and thermodynamics for a variety of problems: nucleation and crystallization processes in vapor and solution, chemical hydrogen storage, and biomass catalysis.

Research Interests

  • Nucleation: Dr. Kathmann is interested in chemical thermodynamics and kinetics of vapor-to-liquid phase transformations as well as crystallization from aqueous solution. This includes aerosol and nano-particle formation, growth, coagulation, transport, crystalloluminescence, charge transfer, scattering of light from aerosols, and the development of systematically improvable interaction potentials for molecular clusters from robust electronic structure calculations with inclusion of anharmonicity and zero-point-energy effects in configuration space sampling.
  • Hydrogen Storage: Dr. Kathmann studies several chemical hydrogen storage materials such as NH4BH4, NH3BH3, LiNH2BH3, NaNH2BH3 (with and without isotope effects) using a combination of theory and experimental measurements (neutron scattering and Raman spectroscopy)
  • Catalysis: Dr. Kathmann studies the nature of Rh-based catalysis with various promoters and how they influence the conversion of biomass-derived syngas to value-added alcohols such as ethanol for use in transportation.

Education and Credentials

  • Dr. Kathmann received his B.S. in Physics in 1991 from Illinois State University and his Ph.D. in Physics from the University of Missouri-Rolla in 1998. His Ph.D. research with Professor Barbara N. Hale at the University of Missouri-Rolla focused on the theoretical description sulfuric acid - water clusters relevant to aerosol formation.
  • In February 1998, Dr. Kathmann joined the Molecular Theory Group as a Postdoctoral Fellow under Dr. Bruce C. Garrett studying the kinetic mechanisms of the nucleation process using Variational Transition State Theory. This work resulted in the development of Dynamical Nucleation Theory.

Affiliations and Professional Service

  • American Chemical Society
  • American Physical Society
  • Materials Research Society

Awards and Recognitions

PNNL Publications


  • Liu J, P Lin, A Laskin, J Laskin, SM Kathmann, ME Wise, R Caylor, F Imholt, V Selimovic, and JE Shilling. 2016. "Optical Properties and Aging of Light Absorbing Secondary Organic Aerosol." Atmospheric Chemistry and Physics 16(19):12815-12827.  doi:10.5194/acp-16-12815-2016
  • Stinson JL, SM Kathmann, and IJ Ford. 2016. "A classical reactive potential for molecular clusters of sulphuric acid and water." Molecular Physics 114(2):172-185.  doi:10.1080/00268976.2015.1090027
  • Wolke CT, JA Fournier, E Miliordos, SM Kathmann, SS Xantheas, and MA Johnson. 2016. "Isotopomer-selective spectra of a single intact H2O molecule in the Cs+(D2O)5H2O isotopologue: Going beyond pattern recognition to harvest the structural information encoded in vibrational spectra ." Journal of Chemical Physics 144(7):074305.  doi:10.1063/1.4941285


  • Lin P, J Liu, JE Shilling, SM Kathmann, J Laskin, and A Laskin. 2015. "Molecular Characterization of Brown Carbon (BrC) Chromophores in Secondary Organic Aerosol Generated From Photo-Oxidation of Toluene." Physical Chemistry Chemical Physics. PCCP 17(36):23312-23325.  doi:10.1039/c5cp02563j
  • Cox SJ, SM Kathmann, B Slater, and A Michaelides. 2015. "Molecular simulations of heterogeneous ice nucleation. I. Controlling ice nucleation through surface hydrophilicity." Journal of Chemical Physics 142(18):184704.  doi:10.1063/1.4919714
  • Cox SJ, SM Kathmann, B Slater, and A Michaelides. 2015. "Molecular Simulations of Heterogeneous Ice Nucleation. II. Peeling back the Layers." Journal of Chemical Physics 142(18):184705.  doi:10.1063/1.4919715
  • Fournier JA, CT Wolke, MA Johnson, TT Odbadrakh, KD Jordan, SM Kathmann, and SS Xantheas. 2015. "Snapshots of Proton Accommodation at a Microscopic Water Surface: Understanding the Vibrational Spectral Signatures of the Charge Defect in Cryogenically Cooled H+(H2O)n=2 28 Clusters." Journal of Physical Chemistry A 119(36):9425-9440.  doi:10.1021/acs.jpca.5b04355


  • Andersen A, SM Kathmann, MA Lilga, KO Albrecht, RT Hallen, and D Mei. 2014. "Effects of Potassium Doping on CO Hydrogenation Over MoS2 Catalysts: A First-Principles Investigation." Catalysis Communications 52:92-97.  doi:10.1016/j.catcom.2014.02.011
  • Kathmann SM, HM Cho, TM Chang, GK Schenter, KK Parab, and T Autrey. 2014. "Experimental and Theoretical Study of Molecular Response of Amine Bases in Organic Solvents ." Journal of Physical Chemistry B 118(18):4883-4888.  doi:10.1021/jp500821u
  • Sellner B, and SM Kathmann. 2014. "A Matter of Quantum Voltages." Journal of Chemical Physics 141(18):Article No. 18C534.  doi:10.1063/1.4898797
  • Stinson JL, SM Kathmann, and IJ Ford. 2014. "Dynamical consequences of a constraint on the Langevin thermostat in molecular cluster simulation." Molecular Physics 112(22):2920-2923.  doi:10.1080/00268976.2014.917732
  • Stinson JL, SM Kathmann, and IJ Ford. 2014. "Investigating the significance of zero-point motion in small molecular clusters of sulphuric acid and water." Journal of Chemical Physics 140(2):024306.  doi:10.1063/1.4860973


  • Albrecht KO, VA Glezakou, RJ Rousseau, MH Engelhard, T Varga, RJ Colby, JE Jaffe, XS Li, D Mei, CF Windisch, Jr, SM Kathmann, TL Lemmon, MJ Gray, TR Hart, BL Thompson, and MA Gerber. 2013. Rh-Based Mixed Alcohol Synthesis Catalysts: Characterization and Computational ReportPNNL-22697, Pacific Northwest National Laboratory, Richland, WA. 
  • Sellner B, M Valiev, and SM Kathmann. 2013. "Charge and Electric Field Fluctuations in Aqueous NaCl Electrolytes ." Journal of Physical Chemistry B 117(37):10869-10882.  doi:10.1021/jp405578w
  • Wen H, GL Hou, SM Kathmann, M Valiev, and XB Wang. 2013. "Communication: Solute Anisotropy Effects in Hydrated Anion and Neutral Clusters." Journal of Chemical Physics 138(3):Article No. 031101.  doi:10.1063/1.4776766


  • Kathmann SM, CJ Mundy, GK Schenter, T Autrey, PC Aeberhard, W David, MO Jones, and T Ramirez-Cuesta. 2012. "Understanding Vibrational Anharmonicity and Phonon Dispersion in Solid Ammonia Borane." Journal of Physical Chemistry C 116(9):5926-5931.  doi:10.1021/jp207540x
  • Andersen A, SM Kathmann, MA Lilga, KO Albrecht, RT Hallen, and D Mei. 2012. "First-principles characterization of potassium intercalation in the hexagonal 2H-MoS2." Journal of Physical Chemistry C 116(2):1826-1832.  doi:10.1021/jp206555b
  • Camaioni DM, B Ginovska-Pangovska, GK Schenter, SM Kathmann, and T Autrey. 2012. "Analysis of the Activation and Heterolytic Dissociation of H2 by Frustrated Lewis Pairs: NH3/BX3 (X = H, F, and Cl) ." Journal of Physical Chemistry A 116(26):7228-7237.  doi:10.1021/jp3039829
  • Cox SJ, SM Kathmann, JA Purton, MJ Gillan, and A Michaelides. 2012. "Non Hexagonal Ice at Hexagonal Surfaces: The Role of Lattice Mismatch." Physical Chemistry Chemical Physics. PCCP 14(22):7944-7949.  doi:10.1039/c2cp23438f
  • Dang LX, GK Schenter, TM Chang, SM Kathmann, and T Autrey. 2012. "Role of Solvents on the Thermodynamics and Kinetics of Forming Frustrated Lewis Pairs." Journal of Physical Chemistry Letters 3(22):3312-3319.  doi:10.1021/jz301533a
  • Glezakou VA, JE Jaffe, RJ Rousseau, D Mei, SM Kathmann, KO Albrecht, MJ Gray, and MA Gerber. 2012. "The Role of Ir in Ternary Rh-Based Catalysts for Syngas Conversion to C2+ Oxygenates." Topics in Catalysis 55(7-10):595-600.  doi:10.1007/s11244-012-9836-9
  • Murdachaew G, M Valiev, SM Kathmann, and XB Wang. 2012. "Study of Ion Specific Interactions of Alkali Cations with Dicarboxylate Dianions." Journal of Physical Chemistry A 116(9):2055-2061.  doi: 10.1021/jp3012848


  • Kathmann SM, IFW Kuo, CJ Mundy, and GK Schenter. 2011. "Understanding the Surface Potential of Water." Journal of Physical Chemistry B 115(15):4369-4377.  doi:10.1021/jp1116036
  • Andersen A, SM Kathmann, MA Lilga, KO Albrecht, RT Hallen, and D Mei. 2011. "Adsorption of Potassium on the MoS2(100) Surface: A First-Principles Investigation." Journal of Physical Chemistry C 115(18):9025-9040.  doi:10.1021/jp110069r


  • Li J, SM Kathmann, HS Hu, GK Schenter, T Autrey, and MS Gutowski. 2010. "Theoretical Investigations on the Formation and Dehydrogenation Reaction Pathways of H(NH2BH2)nH (n=1-4) Oligomers: Importance of Dihydrogen Interactions (DHI)." Inorganic Chemistry 49(17):7710-7720. 
  • Mei D, RJ Rousseau, SM Kathmann, VA Glezakou, MH Engelhard, W Jiang, CM Wang, MA Gerber, JF White, and DJ Stevens. 2010. "Ethanol synthesis from syngas over Rh-based/SiO2 catalysts: A combined experimental and theoretical modeling study." Journal of Catalysis 271(2):325-342. 


  • Kathmann SM, GK Schenter, BC Garrett, B Chen, and JI Siepmann. 2009. "Thermodynamics and Kinetics of Nanoclusters Controlling Gas-to-Particle Nucleation." Journal of Physical Chemistry C 113(24):10354-10370. 
  • Crosby LD, SM Kathmann, and TL Windus. 2009. "Implementation of Dynamical Nucleation Theory with Quantum Potentials." Journal of Computational Chemistry 30(5):743-749. 
  • Fulton JL, SM Kathmann, GK Schenter, and M Balasubramanian. 2009. "Hydrated Structure of Ag(I) Ion from Symmetry-Dependent, K- and L-edge XAFS Multiple Scattering and Molecular Dynamics Simulations." Journal of Physical Chemistry A 113(50):13976-13984. 
  • Hess NJ, GK Schenter, MR Hartman, LL Daemen, TE Proffen, SM Kathmann, CJ Mundy, MA Hartl, DJ Heldebrant, AC Stowe, and T Autrey. 2009. "Neutron Powder Diffraction and Molecular Simulation Study of the Structural Evolution of Ammonia Borane from 15 to 340 K." Journal of Physical Chemistry A 113(9):5723-5735.  doi:10.1021/jp900839c
  • Karkamkar AJ, SM Kathmann, GK Schenter, DJ Heldebrant, NJ Hess, MS Gutowski, and T Autrey. 2009. "Thermodynamic and Structural Investigations of Ammonium Borohydride, a Solid with a Highest Content of Thermodynamically and Kinetically Accessible Hydrogen." Chemistry of Materials 21(19):4356-4358.  doi:10.1021/cm902385c
  • Kathmann SM, VM Parvanov, GK Schenter, AC Stowe, LL Daemen, MA Hartl, JC Linehan, NJ Hess, AJ Karkamkar, and T Autrey. 2009. "Experimental and Computational Studies on Collective Hydrogen Dynamics in Ammonia Borane: Incoherent Inelastic Neutron Scattering." Journal of Chemical Physics 130(2):article no. 024507.  doi:10.1063/1.3042270


  • Kathmann SM, BJ Palmer, GK Schenter, and BC Garrett. 2008. "Activation Energies and Potentials of Mean Force for Water Cluster Evaporation." Journal of Chemical Physics 128(6):Art. No. 064306.  doi:10.1063/1.2837282
  • Kathmann SM, GK Schenter, and BC Garrett. 2008. "The Impact of Molecular Interactions on Atmospheric Aerosol Radiative Forcing." Advances in Quantum Chemistry 55:429-447.  doi:10.1016/S0065-3276(07)00220-1
  • Kathmann SM, GK Schenter, and BC Garrett. 2008. "The Impact of Molecular Interactions on Atmospheric Aerosol Radiative Forcing." Chapter 20 in Applications of Theoretical Methods to Atmospheric Science, Advances in Quantum Chemistry, vol. 55, ed. M Goodsite, M Johnson, J Sabin and E Brandas, pp. 429-447.  Academic Press, Burlington, MA. 
  • Kathmann SM, GK Schenter, and SS Xantheas. 2008. "On the Determination of Monomer Dissociation Energies of Small Water Clusters from Photoionization Experiments." Journal of Physical Chemistry A 112(9):1851-1853.  doi:10.1021/jp710624r
  • Kathmann SM, IFW Kuo, and C Mundy. 2008. "Electronic Effects on the Surface Potential at the Vapor-Liquid Interface of Water." Journal of the American Chemical Society 130(49):16556-16561.  doi:10.1021/ja802851w
  • Cho HM, WJ Shaw, VM Parvanov, GK Schenter, AJ Karkamkar, NJ Hess, CJ Mundy, SM Kathmann, JA Sears, Jr, AS Lipton, PD Ellis, and T Autrey. 2008. "Molecular Structure and Dynamics in the Low Temperature (Orthorhombic) Phase of NH3BH3." Journal of Physical Chemistry A 112(18):4277-4283. 
  • Hess NJ, ME Bowden, VM Parvanov, CJ Mundy, SM Kathmann, GK Schenter, and T Autrey. 2008. "Spectroscopic Studies of the Phase Transition in Ammonia Borane: Raman spectroscopy of single crystal NH3BH3 as a function of temperature from 88 to 330 K." Journal of Chemical Physics 128(3):Art. No. 034508.  doi:10.1063/1.2820768
  • Mundy CJ, RJ Rousseau, A Curioni, SM Kathmann, and GK Schenter. 2008. "A molecular approach to understanding complex systems: computational statistical mechanics using state-of-the-art algorithms on terascale computational platforms ." In SciDAC 2008: Journal of Physics: Conference Series, vol. 125, p. 012014.  IOP Publishing Ltd, Bristol, United Kingdom.  doi:10.1088/1742-6596/125/1/012014
  • Windus TL, SM Kathmann, and LD Crosby. 2008. "High performance computations using dynamical nucleation theory." Journal of Physics: Conference Series 125:012017.  doi:10.1088/1742-6596/125/1/012017


  • Kathmann SM, GK Schenter, and BC Garrett. 2007. "Comment on "Quantum Nature of the Sign Preference in Ion-Induced Nucleation"." Physical Review Letters 98(10) 
  • Kathmann SM, GK Schenter, and BC Garrett. 2007. "The Critical Role of Anharmonicity in Aqueous Ionic Clusters Relevant to Nucleation." Journal of Physical Chemistry C 111(13):4977-4983. 
  • Kathmann SM. 2007. "Nucleation Chemical Physics: From Vapor Phase Clusters to Crystals in Solution." In Nucleation and Atmospheric Aerosols: 17th International Conference, vol. Part 1, ed. CD O'Dowd, PE Wagner, pp. 126-130.  Springer, Dordrecht, Netherlands.  doi:10.1007/978-1-4020-6475-3_25
  • Li J, SM Kathmann, GK Schenter, and MS Gutowski. 2007. "Isomers and Conformers of H(NH2BH2)(n)H Oligomers: Understanding the Geometries and Electronic Structure of Boron-Nitrogen-Hydrogen Compounds as Potential Hydrogen Storage Materials." Journal of Physical Chemistry C 111(8):3294-3299.  doi:10.1021/jp066360b
  • Valiev M, BC Garrett, MK Tsai, K Kowalski, SM Kathmann, GK Schenter, and M Dupuis. 2007. "Hybrid Approach for Free Energy Calculations with High-Level Methods: Application to the S(N)2 Reaction of CHCl3 and OH- in Water." Journal of Chemical Physics 127(5):51102 (1-4). 
  • Mundy CJ, SM Kathmann, and GK Schenter. 2007. "A Special Brew." Natural History 116(9):32-36. 
  • Palmer BJ, SM Kathmann, MK Krishnan, V Tipparaju, and J Nieplocha. 2007. "The Use of Processor Groups in Molecular Dynamics Simulations to Sample Free-Energy States." Journal of Chemical Theory and Computation 3(2):583-592.  doi:10.1021/ct600260u



  • Kathmann SM, GK Schenter, and BC Garrett. 2005. "Ion-Induced Nucleation: The Importance of Chemistry." Physical Review Letters 94(11):116104. 


  • Kathmann SM, GK Schenter, and BC Garrett. 2004. "Multicomponent Dynamical Nucleation Theory And Sensitivity Analysis ." Journal of Chemical Physics 120(19):9133-9141. 


  • Garrett BC, SM Kathmann, and GK Schenter. 2003. "Thermochemistry and kinetics of evaporation and condensation for small water clusters." Chapter 2 in Water in Confining Geometries, ed. V. Buch and J. P. Devlin, pp. 25-51.  Springer-Verlag, New York, NY. 


  • Kathmann SM, GK Schenter, and BC Garrett. 2002. "Understanding the Sensitivity of Nucleation Kinetics: A Case Study on Water." Journal of Chemical Physics 116(12):5046-5057. 
  • Garrett BC, R Bianco, LX Dang, DA Dixon, M Dupuis, J Francisco, B Gertner, JT Hynes, SM Kathmann, TJ Lee, A Morita, KA Peterson, GK Schenter, JH Seinfeld, and SS Xantheas. 2002. A Computational Approach to Understanding Oxidant Chemistry and Aerosol Formation in the TropospherePNNL-14009, Pacific Northwest National Laboratory, Richland, WA. 
  • Schenter GK, SM Kathmann, and BC Garrett. 2002. "Dynamical benchmarks of the nucleation kinetics of water." Journal of Chemical Physics 116(10):4275-4280. 
  • Schenter GK, SM Kathmann, and BC Garrett. 2002. "Equilibrium Constant for Water Dimerization: Analysis of the Partition Function for a Weakly Bound System." Journal of Physical Chemistry A 106(8):1557-1566. 


  • Kathmann SM, and BN Hale. 2001. "Monte Carlo Simulations of Small Sulfuric Acid - Water Clusters." Journal of Physical Chemistry B 105(47):11719-11728. 


  • Kathmann SM, GK Schenter, and BC Garrett. 2000. "Dynamical Nucleation Theory." In Nuclation and Atmospheric Aerosols 2000: 15th International Conference, AIP Conference Proceedings, vol. 534, no. 2000, ed. B. Hale and M. Kulmala, pp. 197-200.  Nucleation and atmospheric Aerosols, Melville, NY. 
  • Kathmann SM, GK Schenter, and BC Garrett. 2000. "Dynamical Nucleation Theory." In Nucleation and Atmospheric Aerosols 2000: 15th International Conference. AIP Conference Proceedings, vol. 534, pp. 1997-2000.  American Institute of Physics, Melville, NY. 


  • Kathmann SM, GK Schenter, and BC Garrett. 1999. "Dynamical Nucleation Theory: Calculation of Condenstion Rate Constants for Small Water Clusters." Journal of Chemical Physics 111(10):4688-4697. 
  • Schenter GK, SM Kathmann, and BC Garrett. 1999. "Variational Transition State Theory of Vapor Phase Nucleation." Journal of Chemical Physics 110(16):7951-7959. 
  • Schenter GK, SM Kathmann, and BC Garrett. 1999. "Dynamical Nucleation Theory: A New Molecular Approach to Vapor-Liquid Nucleation." Physical Review Letters 82(17):3484-3487. 

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