Location: Bowdoin / Ronald L. Christensen

Chemistry

Ronald Christensen

James Stacy Coles Professor of Natural Sciences Emeritus

Contact Information

rchriste@bowdoin.edu
207-725-3604
Chemistry
14 Hatch Science Library


     

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Bowdoin College: RONALD L. CHRISTENSEN : Chemistry

Education

  • A.B. 1967 Oberlin College, Oberlin, Ohio.
  • A.M. 1969 Harvard University, Cambridge, Massachusetts.
  • Ph.D. 1972 Harvard University, Cambridge, Massachusetts.

Research Interests

Physical chemistry, photobiology, organic photochemistry and low temperature, electronic spectroscopy.

Ronald Christensen's personal page »

Curriculum vitae in PDF formpdf »

(undergraduate co-authors are indicated by *s)

Energetics and Dynamics of the Low-Lying Electronic States of Constrained Polyenes: Implications for Infinite Polyenes,” R.L. Christensen, M.M. Enriquez,  N.L. Wagner, A.Y. Peacock-Villada,* C. Scriban, R.R. Schrock, Tomáš Polívka, H.A. Frank, and R.R. Birge, Journal of Physical Chemistry A, 117, 1449-1465 (2013).

A Case of Reform: The Undergraduate Research Collaboratives,” E. Horsch, M. St. John, and R. L. Christensen, Journal of College Science Teaching 41, 14-19 (2012).

"Ultrafast Excited State Relaxation in Long-chain Polyenes," M. R. Antognazza, L. Lüer, D. Polli, R. L. Christensen, R. R. Schrock, G. Lanzani, and G. Cerullo, Chemical Physics 373, 115-121 (2010).

Synthesis and Optical Spectroscopy of Oligo (1,6-Heptadiynes) with a Single Basic Structure Prepared Through Adamantylimido-based Molybdenum Wittig and Metathesis Chemistry,” C. Scriban, B. S. Amagai,* E. A. Stemmler, R. L. Christensen, and R. R. Schrock, Journal of the American Chemical Society, 131, 13441-13452 (2009).

"Excited Electronic States and the Photochemistry and Photophysics of Carotenoids," H.A. Frank and R.L. Christensen in Carotenoids, Vol. 4:  Natural Functions, G. Britton, S. Liaaen-Jensen, and H. Pfander (eds.), Springer, pp.167-188 (2008).

"Energies of Low-Lying Excited States of Linear Polyenes," R.L. Christensen, M.G.I. Galinato, E.F. Chu,* J.N. Howard,* R.D. Broene, and H.A. Frank, J. Phys. Chem. A 2008, 112, 12629-12636 (2008).

"Symmetry Control of Radiative Decay in Linear Polyenes: Low Barriers for Isomerization in the S1 State of Hexadecaheptaene," R.L. Christensen, M.G.I. Galinato, E.F. Chu,* R. Fujii, H. Hashimoto, and H. A. Frank, J. Am. Chem. Soc., 129 (6), 1769 -1775 (2007).

"Synthesis of Oligoenes that Contain up to 15 Double Bonds from 1,6-Heptadiynes," C. Czekelius, J. Hafer, Z. J. Tonzetich, R. R. Schrock, R.L. Christensen, and P. Müller, J. Am. Chem. Soc., 128 (51), 16664 -16675 (2006).

"Femtosecond Time-Resolved Absorption Spectroscopy of Astaxanthin in Solution and in α-Crustacyanin," R.P. Ilagan, R.L. Christensen, T.W. Clapp,* G.N. Gibson, T. Pascher, T. Polivka, and H.A. Frank, Journal of Physical Chemistry A 109, 3120-3127 (2005).

Optical Spectroscopy of Long Polyenes,” R.L. Christensen, A Faksh*, J. Meyers*, I.F.W. Samuel, P. Wood, K. Hultzsch, and R.R. Schrock, Journal of Physical Chemistry A 108, 8229-8236 (2004).

Linear Polyenes: Models for the Spectroscopy and Photophysics of Carotenoids,” R. L. Christensen, E. A. Barney*, R. D. Broene, M. G. I. Galinato*, and H. A. Frank, Archives of Biochemistry and Biophysics 430, 30-36 (2004).

"Spectroscopic and Photochemical Properties of Open-Chained Carotenoids," H.A. Frank, J.S. Josue*, J.A. Bautista*, I. van der Hoef, F.J. Jansen, J. Lugtenburg, G. Wiederrecht, and R.L. Christensen, Journal of Physical Chemistry B 106, 2083-2092 (2002).

"Conformational Disorder in Long Polyenes," P. Wood*, I.D.W. Samuel, R. Schrock, and R.L. Christensen, Journal of Chemical Physics 115, 10955-10963 (2001).

"The Electronic States of Carotenoids," R.L. Christensen in The Photochemistry of Carotenoids, H.A. Frank, A.J. Young, G. Britton, and R.J. Cogdell (eds.), Kluwer Academic Publishers, pp.137-160 (1999).

"The Rotationally Resolved Electronic Spectra of all-trans-Octatetraene and its Derivatives," J.F. Pfanstiel, D.W. Pratt, B.A. Tounge*, and R.L. Christensen, Journal of Physical Chemistry A 103, 2337-2347 (1999).

"S1 and S2 States of Apo- and Diapocarotenes," R.L. Christensen, M. Goyette*, L. Gallagher*, J. Duncan*, B. DeCoster, J. Lugtenburg, F.J. Jansen, and I. van der Hoef, Journal of Physical Chemistry A 103, 2399-2407 (1999).

"Time-Resolved Luminescence Anisotropy Studies of the Relaxation Behavior of Polymers. 1. Intramolecular Segmental Relaxation of Poly(methyl methacrylate) and Poly(methacrylate) in Dilute Solutions in Dichloromethane," I. Souter, L. Swanson, R.L. Christensen, R.C. Drake*, and D. Phillips, Macromolecules 29, 4931-4936 (1996).

"One- and Two-photon Fluorescence Excitation Spectra of the 21Ag States of Linear Tetraenes in Free Jet Expansions," H. Petek, A.J. Bell, Y.S. Choi, K. Yoshihara, B.A. Tounge*, and R.L. Christensen, Journal of Chemical Physics 102, 4726 (1995).

"Singlet Energy Transfer from Carotenoids to Bacteriochlorophylls," H.A. Frank and R.L. Christensen, in Anoxygenic Photosynthetic Bacteria (R.E. Blankenship, M.T. Madigan, and C.E. Bauer, eds.), Kluwer Academic Publishers, pp.373-384 (1995).

"A New Homogeneous Assay System for Specific Nucleic Acid Sequences: poly-dA and poly-A Detection," C.B. Bagwell, M E. Munson, R.L. Christensen, and E.J. Lovett, Nucleic Acids Research 22, 2424 (1994).

"Evidence for quantization of the transition state for cis-trans isomerization," Y.S. Choi, T.-S. Kim, H. Petek, K. Yoshihara, and R.L. Christensen, Journal of Chemical Physics 100, 9269 (1994).

"The 21Ag State of trans,trans-1,3,5,7-octatetraene in Free Jet Expansions," H. Petek, A.J. Bell, Y.S. Choi, K. Yoshihara, B. Tounge*, and R.L. Christensen, Journal of Chemical Physics 98, 3777 (1993).

"Carotenoid-to-Bacteriochlorophyll Singlet Energy Transfer in Carotenoid-Incorporated B850 Light-Harvesting Complexes of Rhodobacter Sphaeroides R26.1," H.A. Frank, R. Farhoosh, M. Aldema, B. DeCoster, R.L. Christensen, R. Gebhard, and J. Lugtenburg, Photochemistry and Photobiology 57, 49 (1993).

"Low Lying Electronic States of Carotenoids," B. DeCoster, R.L. Christensen, R. Gebhard, J. Lugtenburg, R. Farhoosh, and H. Frank, Biochimica et Biophysica Acta 1102, 107 (1992).

"Vibrational Spectroscopy and Picosecond Dynamics of Gaseous Trienes and Tetraenes in S1 and S2 Electronic States," H. Petek, A.J. Bell, R.L. Christensen, and K. Yoshihara, SPIE 1638 (Optical Methods for Time- and State-Resolved Chemistry), 345 (1992).

"Spectroscopy and Dynamics of a Model Polyene Decatetraene: A Study of Non-Radiative Pathways in S1 and S2 States under Isolated Conditions," H. Petek, A.J. Bell, H. Kandori, K. Yoshihara, and R.L. Christensen, in Time-Resolved Vibrational Spectroscopy V; H. Takahashi, Ed.; Springer-Verlag; Berlin. p. 198 (1992).

"Fluorescence Excitation Spectra of the S1 States of Isolated Trienes," H. Petek, A.J. Bell, R.L. Christensen, and K. Yoshihara, Journal of Chemical Physics 96, 2412 (1992).

"Spectroscopic and Dynamical Studies of the S1 and S2 states of Decatetraene in Supersonic Molecular Beams," H. Petek, A. Bell, K. Yoshihara, and R. Christensen, Journal of Chemical Physics 95, 4739 (1991).

"Electronic Relaxation in Long Polyenes," S.A. Cosgrove*, M.A. Guite*, T.B. Burnell*, and R.L. Christensen, Journal of Physical Chemistry 94, 8118 (1990).

"Fluorescence of Gaseous Tetraenes and Pentaenes," W. Bouwman, A. Jones, D. Phillips, P. Thibodeau*, C. Friel*, and R. Christensen, Journal of Physical Chemistry 94, 7429 (1990).

"Effects of Hydrogen Bonding on the Low Lying Electronic States of a Model Polyene Aldehyde," J. Papanikolas*, G. Walker*, V. Shamamian*, J.C. Baum, and R. Christensen, Journal of the American Chemical Society 112, 1912 (1990).

2005-07   Program Officer, Division of Chemistry, Directorate for Mathematical and Physical Sciences, the National Science Foundation
2003-04   Visiting Professor, Department of Chemistry, University of Connecticut.
2003       American Chemical Society Award for Research at an Undergraduate Institution.
2000-03   Associate Dean for Academic Affairs for the Sciences, Bowdoin College.
1999-       James Stacy Coles Professor of Natural Sciences, Bowdoin College.
1998       Visiting Professor, Department of Chemistry, Imperial College, London.
1993-95   Chair, Department of Chemistry, Bowdoin College.
1989-90   Visiting Research Fellow in Department of Physical Chemistry, The University of Melbourne, Australia. Visiting Professor, Institute for Molecular Science, Okazaki, Japan.
1988-       Professor of Chemistry, Bowdoin College.
1987-89   Chair, Department of Chemistry, Bowdoin College.
1982-88   Associate Professor of Chemistry, Bowdoin College.
1982-83   Visiting Professor, Royal Institution of Great Britain, London - time resolved fluorescence and fluorescence anisotropy of synthetic polymers and biological membranes.
1980-82   Director, Bowdoin College Summer Course, Fluorescence Spectroscopy: Techniques and Applications.
1976-82   Assistant Professor of Chemistry, Bowdoin College.
1975-76   Research Fellow in Chemistry, Wesleyan University, Middletown, Connecticut- high resolution optical spectroscopy of linear polyenes.
1973-75   Research Fellow at the Rijksuniversiteit, Leiden, the Netherlands - low temperature studies of molecular crystals using high resolution optical spectroscopy, epr, and zero-field optical-magnetic double resonance.
1970-72   Sanger Research Fellow, Harvard University.
1967-70   Teaching Fellow in undergraduate chemistry courses, Harvard University.