Professor of Chemistry and Physics
About
Making Molecular Movies: Light, Molecules, Action.
Light provides a versatile energy source capable of precise manipulation of material systems on size scales ranging from molecular to macroscopic. Photochemistry provides the means for harnessing light energy through the movement of charge, a change in molecular shape, or the cleavage of a bond. Photochemistry produces action. The potential for optically powered molecular devices covers a wide range of applications, from motors, and switches, to sensors and delivery platforms. Cobalamins and other cyclic tetrapyrroles can provide spatial and temporal control of radical formation, charge transfer, and drug delivery. Water soluble photoacids are capable of providing control of the local pH on an ultrashort time scale.
The practical development of optically controlled molecular devices faces a range of challenges. In our group we use time-resolved spectroscopic methods coupled with theoretical simulations to investigate, predict, and control the photochemistry of important light-activated transformations. Femtosecond transient absorption spectroscopy in the UV-visible region of the spectrum is used to characterize time-scales and monitor product formation. State-of-the-art femtosecond X-ray studies carried out at X-ray free electron laser facilities such as LCLS at SLAC allow the direct observation of structural evolution beginning at the very earliest times.
Representative Publications
Sofferman, D. L., Konar, A., Mastron, J. N., Spears, K. G., Cisneros, C., Smith, A. C., Tapavicza, E., and Sension R. J., “Probing the formation and conformational relaxation of previtamin D3 and analogs in solution and in lipid bilayers.” 2021, The Journal of Physical Chemistry B, 125, 10085-10096. DOI: 10.1021/acs.jpcb.1c04376
Aldaz, C. R., Wiley, T. E., Miller, N. A., Abeyrathna. N., Liao, Y. Zimmerman, P. M. and Sension, R. J., “Experimental and theoretical characterization of ultrafast water-soluble photochromic photoacids.” 2021, The Journal of Physical Chemistry B, 125, 4120-4131. DOI: 10.1021/acs.jpcb.1c00644
Sofferman, D. L., Konar, A., Spears, K. G., Sension R. J., “Ultrafast excited state dynamics of provitamin D3 and analogs in solution and in lipid bilayers.” 2021, Journal of Chemical Physics, 154, 094309. DOI: 10.1063/5.0041375
Miller, N.A., Kaneshiro, A.K., Konar, A., Alonso-Mori, R., Britz, A., Deb, A., Glownia, J.M., Koralek, J.D., Mallik, L., Meadows, J.H., Michocki, L.B., van Driel, T.B., Koutmos, M., Padmanabhan, S., Elías-Arnanz, M., Marsh, E.N.G., Kubarych, K. J., Penner-Hahn, J.E. and Sension, R.J., “The photoactive excited state of the B12-based photoreceptor CarH” The Journal of Physical Chemistry B, 124, 10732-10738. DOI: 10.1021/acs.jpcb.0c09428
Sension, R. J., 2020, “Visualizing ultrafast chemical dynamics with X-rays” Proceedings of the National Academy of Sciences, USA, 117, 26550-26552. DOI: 10.1073/pnas.2017806117
Salerno, E.V., Miller, N.A., Konar, A., Li, Y., Kieninger, C., Kräutler, B., and Sension, R.J. 2020 “Ultrafast excited state dynamics and fluorescence from vitamin B12 and organometallic [Co]-CºC-R Cobalamins” The Journal of Physical Chemistry B, v. 124, 6651-6656. DOI: 10.1021/acs.jpcb.0c04886
Salerno, E.V., Miller, N.A., Konar, A., Salchner, R., Kieninger, C., Wurst, K., Spears, K.G., Kräutler, B., and Sension, R.J. 2020, “Exceptional Photochemical Stability of the Co-C Bond of Alkynyl Cobalamins, Potential Antivitamins B12 and Core Elements of B12-Based Biological Vectors” Inorganic Chemistry, v. 59, 6422-6431. DOI: 10.1021/acs.inorgchem.0c00453
Miller, N.A., Michocki, L.B., Konar, A., Alonso-Mori, R., Deb, A., Glownia, J.M., Sofferman, D.L., Song, S., Kozlowski, P. M., Kubarych, K. J., Penner-Hahn, J.E. and Sension, R.J. 2020, “Ultrafast XANES Monitors Sequential Structural Evolution in Photoexcited Coenzyme B12” Journal of Physical Chemistry B., v.124, 199-209. DOI: 10.1021/acs.jpcb.9b09286
Miller, N.A., Michocki, L.B., Alonso-Mori, R., Britz, A., Deb, A., DePonte, D.P., Glownia, J.M., Kaneshiro, A.K., Kieninger, C., Koralek, J., Meadows, J.H., van Driel, T.B., Kräutler, B., Kubarych, K. J., Penner-Hahn, J.E. and Sension, R.J., 2019, “Antivitamins B12 in a microdrop: The excited state structure of a precious sample using transient polarized X-ray absorption near edge structure” Journal of Physical Chemistry Letters, v 10, 5484-5489. DOI: 10.1021/acs.jpclett.9b02202
Michocki, L. B., Miller, N. A., Alonso-Mori, R., Britz, A., Deb, A., Glownia, J. M., Kaneshiro, A. K., Konar, A., Meadows, J. H., Sofferman, D. L., Song, S., Toda, M. J., van Driel, T. B., Kozlowski, P. M., Kubarych, K. J., Penner-Hahn, J. E., Sension, R. J., 2019, “Probing the excited state of methylcobalamin using polarized time-resolved X-ray absorption spectroscopy.” Journal of Physical Chemistry B, v123, 6042-6048. DOI: 10.1021/acs.jpcb.9b05854
Wiley, T.E., Konar, A., Miller, N.A., Spears, K. G. and Sension R. J., 2018, “Primed for Efficient Motion: Ultrafast Excited State Dynamics and Optical Manipulation of a Four Stage Rotary Molecular Motor” Journal of Physical Chemistry A, v122, 7548-7558. DOI:10.1021/acs.jpca.8b06472
Wiley, T.E., Miller, N.A., Miller, W. R., Sofferman, D., Lodowski, P., Toda, M. J., Jaworska, M., Kozlowski, P. M. and Sension, R. J., 2018, “Off to the races: Comparison of excited state dynamics in vitamin B12 derivatives hydroxocobalmin and aquocobalamin” Journal of Physical Chemistry A, v122, 6693-6703. DOI: 10.1021/acs.jpca.8b06103
Miller, N.A., Deb, A., Alonso-Mori, R., Glownia, J.M., Kiefer, L.M., Konar, A., Michocki, L., Sikorski, M., Sofferman, D., Song, S., Toda, M.J., Wiley, T.E., Zhu, D., Kozlowski, P.M., Kubarych, K.J., Penner-Hahn, J.E. and Sension, R.J. 2018, “Ultrafast X-Ray Absorption Near Edge Structure Reveals Ballistic Excited State Structural Dynamics” Journal of Physical Chemistry A, v122, 4963-4971. DOI: 10.1021/acs.jpca.8b04223
Miller, N.A., Deb, A., Alonso-Mori, R., Garabato, B.D., Glownia, J.M., Kiefer, L.M., Koralek, J., Sikorski, M., Spears, K.G., Wiley, T.E., Zhu, D., Kozlowski, P.M., Kubarych, K.J., Penner-Hahn, J.E. and Sension, R.J. 2017, “Polarized XANES Monitors Femtosecond Structural Evolution of Photoexcited Vitamin B12.” Journal of the American Chemical Society, v139, 1894-1899. DOI: 10.1021/jacs.6b11295
Miller, N.A., Wiley, T.E., Spears, K.G., Ruetz, M., Kieninger, C., Kräutler, B., and Sension R.J., 2016, “Toward the Design of Photoresponsive Conditional Antivitamins B12: A Transient Absorption Study of the Photochemistry of an Arylcobalamin and an Alkynylcobalamin.” Journal of the American Chemical Society, v138, 14250-14256. DOI: 10.1021/jacs.6b05299
Research Areas(s)
- Bioinorganic Chemistry
- Biophysical Chemistry
- Chemical Biology
- Energy Science
- Optics and Imaging
- Physical Chemistry
- Photochemistry
- Sustainable Chemistry
- Ultrafast Dynamics
- Ultrafast Laser Spectroscopy and Chemical Reaction Dynamics
Award(s)
- American Association for the Advancement of Science (AAAS) Fellow
- Mildred Dresselhaus Award, CUI-Hamburg, 2014
- American Physical Society Fellow, 2007
- LSA Excellence in Education Award, 2005