Molecular Spectroscopy Laboratory

Spectroscopy is the "eyes" of modern science, and hence it plays essential roles in a variety of research fields covering physics, chemistry and biology. We develop and utilize the most advanced spectroscopy for molecular science of complex systems in the condensed-phase. To elucidate a variety of complex phenomena occurring in the condensed phase, we need to clarify the electronic and vibrational states of molecules, the response of surroundings, and the fluctuation and dissipation of energy behind. Based on this view, we carry out fundamental research using the most advanced linear/nonlinear spectroscopic methods with most suitable time- and space-resolution for the problems to be studied. Currently, we are carrying out the following projects:
1. Elucidation and control of ultrafast phenomena using advanced time-resolved spectroscopy,
2. Study of soft interfaces using new nonlinear spectroscopy,
3. Study of the dynamics of complex systems in the femtosecond - millisecond time region.
Targets of the projects 1, 2, 3 are (1) fundamental molecules in solution, (2) molecules at the air/liquid, liquid/liquid, liquid/solid and biological interfaces, and (3) biological macromolecules, respectively.

Research Subjects

• Elucidation and control of ultrafast phenomena using advanced time-resolved spectroscopy
• Study of soft interfaces using new nonlinear spectroscopy
• Study of the dynamics of complex systems in the femtosecond - millisecond time region.

Publications

1. Yamaguchi, S. Kundu, A. Sen, P. Tahara, T.:
   "Quantitative estimate of the water surface pH using heterodyne-detected electronic sum freqeuncy generation"
   J. Chem. Phys., 137, 151101/1-4 (2012)
2. Singh, P. C. Nihonyanagi, S. Yamaguchi, S. Tahara, T.:
   "Ultrafast vibrational dynamics of water at a charged interface revealed by two-dimensional heterodyne-detected vibrational sum frequency generation"
   J. Chem. Phys., 137, 094706/1-6 (2012)
3. Mondal, J. Nihonyanagi, S. Yamaguchi, S. Tahara, T.:
   "Three distinct water structures at a zwitterionic lipid/water interface revealed by heterodyne-detected vibrational sum frequency generation"
   J. Am. Chem. Soc., 134(8), 7842-7850 (2012)
4. Nihonyanagi, S., Ishiyama, T., Lee, T., Yamaguchi, S., Bonn, M., Morita, A., Tahara, T.:
   "Unified molecular view of air/water interface based on experimental and theoretical χ(2) spectra of isotopically diluted water surface"
   J. Am. Chem. Soc., 133(42), 16875-16880 (2011)
5. Wei, Z., Nakamura, T., Takeuchi, S., Tahara, T.:
   "Tracking of the nuclear wavepacket motion in cyanine photoisomerization by ultrafast pump-dump-probe spectroscopy"
   J. Am. Chem. Soc., 133(21), 8205-8210 (2011)
6. Iwamura, M., Watanabe, H., Ishii, K., Takeuchi, S., Tahara, T.:
   "Coherent nuclear dynamics in ultrafast photoinduced structural change of bis(diimine)copper(I) complex"
   J. Am. Chem. Soc., 133(20), 7728-7736 (2011)
7. Nihonyanagi, S., Yamaguchi, S. and Tahara, T.:
   "Water hydrogen bond structure near highly charged interfaces is not like ice"
   J. Am. Chem. Soc., 132, 6867 (2010)
8. Nihonyanagi, S., Yamaguchi, S. and Tahara, T.:
   "Direct evidence for orientational flip-flop of water molecules at charged interfaces: a heterodyne-detected vibrational sum frequency generation study"
   J. Chem. Phys., 130, 204704 (2009)
9. Takeuchi, S., Ruhman, S., Tsuneda, T., Chiba, M., Taketsugu, T. and Tahara, T.:
   "Spectroscopic tracking of structural evolution in ultrafast stilbene photoisomerization"
   Science 322,1073 (2008)
10. Takeuchi, S. and Tahara, T.:
    "The answer to concerted versus step-wise controversy for double proton transfer mechanism of 7-azaindole dimer in solution"
    Proc. Natl. Acad. Sci. USA, 104, 5285 (2007)