Kana Takematsu

Assistant Professor of Chemistry and Biochemistry

Teaching this semester

CHEM 1109. General Chemistry

A one-semester introductory chemistry course. Introduction to models of atomic structure, chemical bonding, and intermolecular forces; characterization of chemical systems at equilibrium and spontaneous processes; the rates of chemical reactions; and special topics. Lectures, review sessions, and four hours of laboratory work per week. Students who have taken Chemistry 1102 may not take Chemistry 1109 for credit. To ensure proper placement, students must take the chemistry placement examination and must be recommended for placement in Chemistry 1109.

CHEM 3510. Advanced Topics in Physical and Biophysical Chemistry

Explores reactivity and kinetics from a physical chemistry perspective. We will survey theories and applications to model observed synthetic, gas phase, surface, and biological reactions. In particular, we will utilize a molecular picture to rationalize current and past discoveries in chemistry. Planned topics include aspects of the isotope effect and tunneling in catalysis, potential energy surfaces and molecular dynamic models, photochemistry and conical intersections, reaction dynamics and molecular beam experiments, enzymology, surface catalysis, polymer-binding, and charge-transfer models. Emphasis will be placed on reading and discussing scientific literature.

Kana Takematsu became interested in physical chemistry after working in Laurie Butler’s lab to investigate gas phase dynamics during her undergraduate studies at University of Chicago. She pursued her interests in graduate school at Caltech, working with Mitchio Okumura to study the spectroscopy and kinetics of gas phase intermediates in the Earth’s atmosphere. She then joined Harry Gray’s group at Caltech for her postdoctoral work to extend her training to the condensed phase, studying charge transfer processes in metal-modified azurin mutants and inorganic complexes. In July 2015, she joined the Department of Chemistry at Bowdoin College as an assistant professor in chemistry and biochemistry.

Education

  • Ph.D., California Institute of Technology; Pasadena, CA
  • B.S., University of Chicago; Chicago, IL

Our Group Research

Electron and proton transfer (ET/PT) are two of the most fundamental processes in chemistry. Proton-coupled ET (PCET) refers to reactions involving the exchange and release of both proton and electron species. These reactions play significant roles in biological processes (e.g. respiration, nitrogen fixation, photosynthesis), organic synthesis (e.g. hydrogen atom transfer), and solar fuel and artificial photosynthesis (e.g. catalysis). Our group is interested in tackling the problem of charge transfer processes using a variety of spectroscopic and computational tools. We are also open to collaborations, especially interdisciplinary research, as we value the unique contributions that each scientist or investigator brings to a problem.

Our current project:

Photoacids, molecules which increase in acidity upon electronic excitation, are ideal candidates for controlled PT studies. They have been investigated as possible proton generators and fluorescence pH/chemical probes for biological study. Application of green fluorescent proteins (GFP) for fluorescence imaging and chemical sensing have revolutionized the field of molecular cellular biology. The chromophore of GFP is a photoacid whose remarkable quantum yield is a result of excited state stabilization by the protein matrix. Thus, there is considerable interest in understanding both the PT and photodecay processes of photoacids in a lipid/protein framework.

We focus on examining inter- and intramolecular PT mechanisms of photoacids with multi-proton binding sites in different solvent and increasing complex environments, including reverse micelles and proteins. Fluorescence spectroscopy is an extremely sensitive analytical technique that can probe both excited state dynamics and changes in the environment. We will use a combination of steady-state fluorescence spectroscopy and time-correlated single photon counting to investigate PT.

Selected Publications

Tryptophan-accelerated electron flow across a protein-protein interface 
K. TakematsuŦ, H. R. WilliamsonŦ, A. M. Blanco-Rodríguez, L. Sokolová, P. Nikolovski, J. T. Kaiser, M. Towrie, I. P. Clark, A. Vlček, J. R. Winkler, H. B. Gray. JACS, 2013, 135, 15515-15525.

Spectroscopic studies of the Jahn Teller effects in the 2Eʺ Ã state of the nitrate radical NO3
K. Takematsu, N. C. Eddingsaas, D. R. Robichaud, and M. Okumura. Chem. Phys. Lett., 2013, 555, 57-63.

Competing pathways in the 248 nm photodissociation of propionyl chloride and the barrier to dissociation of the propionyl radical
L. R. McCunn, M. J. Krisch, K. Takematsu, L. J. Butler, F. R. Blasé, and J. Shu. J. Phys. Chem. A, 2004, 108, 7880-7894.

Photodissociation of CH3OCl to CH3O at 248 nm
M. J. Krisch, L. R. McCunn, K. Takematsu, L. J. Butler, F. R. Blasé, and J. Shu. J. Phys. Chem. A, 2004, 108, 1650-1656.

Student Research

The Takematsu group is always open to undergraduate students excited about exploring charge transfer processes in a research environment! The Chemistry Department further encourages students to engage in research through independent study, honors project, and summer research. If you are interested in joining the Takematsu Research Family, please contact: ktakemat@bowdoin.edu.