J. Charles Williamson

Professor of Chemistry, Taul Watanabe Chair in the Sciences
Specialty: Physical Chemistry


  • B.S., Harvey Mudd College
  • Ph.D., California Institute of Technology


Professional Interests

Time-resolved laser spectroscopy and molecular dynamics; scattering and diffraction techniques; thermodynamics of non-ideal binary mixtures

Characterization of liquid-liquid coexistence curves by laser light scattering

Assessment of solvent shell structure and microscopic interactions in liquid-liquid mixtures using Raman spectroscopy

Nanosecond time-resolved investigations of fluorescence up-conversion from mixtures of ruthenium compounds and organic molecules

Development of NMR spectroscopy techniques for studying liquid-liquid behavior

Raman spectroelectrochemical investigations of Ru(II) and Ru(III) anti-cancer compounds, (in collaboration with Professor Holman)


  • J. C. Williamson, Alison M. Brown, Elsie N. Helvie, and Kevin M. Dean, “Determination of Liquid-Liquid Critical Point Composition Using 90° Laser Light Scattering,” Phys. Rev. E, 93, 042610 (2016).
  • J. C. Williamson, T. S. Kuntzleman, and R. A. Kafader, “A Molecular Iodine Spectral Data Set for Rovibronic Analysis,”  Journal of Chemical Education, 90(3), 383-385 (2013).
  • J. C. Williamson, “Molecular Iodine Fluorescence Using a Green Helium-Neon Laser,” J. Chem. Educ., 88(6), 816-818 (2011).
  • K. M. Dean and J. C. Williamson, “The Stir-Settle Approach to Semiautomated Light Scattering Determination of Liquid-Liquid Coexistence Curves,” J. Chem. Eng. Data, 56(4), 1433-1437 (2011).
  • J. C. Williamson, "Molecular Iodine Fluorescence Spectra Generated with Helium-Neon Lasers for Spectrometer Calibration," Appl. Spectrosc., 64(12), 1419-1422 (2010).
  • K. M. Dean, C. B. Babayco, D. R. B. Sluss, and J. C. Williamson, "The Accuracy of Liquid-Liquid Phase Transition Temperatures Determined from Semiautomated Light Scattering Measurements," J. Chem. Phys. 133, 074506 (2010).
  • J. G. Lambert, C. Hernandez-Diaz, and J. C. Williamson, "Subwavenumber Charge-Coupled Device Spectrometer Calibration Using Molecular Iodine Laser-Induced Fluorescence, " Rev. Sci. Instrum.81, 013110 (2010).
  • J. C. Williamson, "Interactive Two-Component Phase Diagrams," J. Chem. Educ. 86(5), 653-654 (2009).
  • J. C. Williamson, "Teaching the Rovibronic Spectroscopy of Molecular Iodine," J. Chem. Educ. 84(8), 1355-1359 (2007).
  • J. C. Williamson, R. Torres-Isea, and C. A. Kletzing, "Analyzing Linear and Angular Momentum Conservation in Digital Videos of Puck Collisions," Amer. J. Phys. 68(9), 841-847 (2000).
  • J. C. Williamson, J. Cao, H. Ihee, H. Frey, and A. H. Zewail, "Clocking Transient Chemical Changes By Ultrafast Electron Diffraction," Nature, 386, 159-162 (1997).
  • M. Dantus, S. B. Kim, J. C. Williamson, and A. H. Zewail, "Ultrafast Electron Diffraction 5: Experimental Time Resolution and Applications," J. Phys. Chem. 98(11), 2782-2796 (1994).
  • J. C. Williamson and A. H. Zewail, "Ultrafast Electron Diffraction 4: Molecular Structures and Coherent Dynamics," J. Phys. Chem. 98(11), 2766-2781 (1994).