田原分子分光研究室 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 our fundamental research using the most advanced linear/nonlinear spectroscopic methods with most suitable time- and space-resolution for the problems to be studied.

Director: Tahei Tahara



Observation and elucidation of ultrafast molecular dynamics by advanced time-resolved spectroscopy
Tracking the molecular dynamics from the electronic and structural viewpoints is essential for deep understanding of chemical reactions. To this end, we develop new ultrafast spectroscopic methods based on basic knowledge on the light-matter interaction and state-of-the-art laser technology. Using these advanced spectroscopy, we aim to observe, understand, and control new fundamental phenomena of reactive molecules.



Developments of novel inteface-selective nonlinear spectroscopies and elucidations of molecular mechanisms of interfacial phenomena
Emergences of novel experimental techniques often open new doors for finding new phenomena as well as unknown mechanisms, especially for microscopic elucidations. In our group, by developing new techniques based on the even-order nonlinear optics, we investigate the structures and dynamics of molecules at interfaces. Our studies are opening up a new field of interfacial science.



Development of novel single-molecule methods and application to elucidate complex behavior of biomolecular systems
The single-molecule spectroscopy group is engaged in the development of new methods of single-molecule fluorescence spectroscopy and related photon data analysis. By utilizing the developed methods, we investigate the complex behavior of biomolecular systems, such as proteins, nucleic acids, and lipid membranes. Through the integrated approach of laser spectroscopy, biophysical chemistry, and statistical data analysis, we pursue creating a new field of molecular science.


Ultrafast Raman observation of the perpendicular intermediate phantom state of stilbene photoisomerization

H. Kuramochi, T. Tsutsumi, K. Saita, Z. Wei, M. Osawa, P. Kumar, L. Liu, S. Takeuchi, T. Taketsugu, and T. Tahara, Nat. Chem. 16, 22-27 (2024).

Front Cover

Microsecond folding of preQ1 riboswitch and its biological significance revealed by two-dimensional fluorescence lifetime correlation spectroscopy

B. Sarkar, K. Ishii, and T. Tahara, J. Am. Chem. Soc. 143, 7968-7978 (2021).

The photochemical reaction of phenol becomes ultrafast at the air–water interface

R. Kusaka, S. Nihonyanagi and T. Tahara, Nat. Chem. 13, 306–311 (2021).

Front Cover

Elucidation of the pH-Dependent Electric Double Layer Structure at the Silica/Water Interface Using Heterodyne-Detected Vibrational Sum Frequency Generation Spectroscopy

F. Wei, S.-h. Urashima, S. Nihonyanagi, and T. Tahara, J. Am. Chem. Soc. 145, 8833 (2023).