CHEMISTRY LETTERS 44(8) 1059-1061 Aug 2015 [Refereed]
The energies of low-lying singlet excited states of oligothiophenes, xT's (x = 3 to 8), and polythiophene are determined using femtosecond time-resolved near-infrared spectroscopy. The energies are linearly correlated with the reciprocal number of...
Ashok Zachariah Samuel   Sohshi Yabumoto   Kenichi Kawamura   Koichi Iwata   
ANALYST 140(6) 1847-1851 2015 [Refereed]
Raman imaging is one of the very informative methods for the characterization of chemically and structurally heterogeneous materials without employing specific molecular labels. Multifocus Raman imaging is one of the fast-imaging alternatives to t...
JOURNAL OF PHYSICAL CHEMISTRY B 118(29) 8631-8641 Jul 2014 [Refereed]
A number of biochemical reactions proceed inside biomembranes. Because the rate of a chemical reaction is influenced by chemical properties of the reaction field, it is important to examine the chemical properties inside the biomembranes, or lipid...
JOURNAL OF PHYSICAL CHEMISTRY A 118(23) 4071-4078 Jun 2014 [Refereed]
Carotenoids have two major low-lying excited states, the second lowest (S-2 (1B(u)(+))) and the lowest (S-1 (2A(g)(-))) excited singlet states, both of which are suggested to be involved in the energy transfer processes in light-harvesting complex...
JOURNAL OF RAMAN SPECTROSCOPY 39(11) 1512-1517 Nov 2008 [Refereed]
Ultrafast bimolecular radical reaction proceeds between photoexcited p-terphenyl and carbon tetrachloride. The lifetime of the first excited singlet (Si) state of p-terphenyl in carbon tetrachloride measured with picosecond time-resolved fluoresce...
Wenjuan Xiong   Lili Du   Kin Cheung Lo   Haiting Shi   Tomohisa Takaya   Koichi Iwata   Wai Kin Chan   David Lee Phillips   
JOURNAL OF PHYSICAL CHEMISTRY LETTERS 9(14) 3819-3824 Jul 2018
Conjugated polymers incorporated with cycloplatinated complexes (P1-Pt and P2-Pt) were used as dispersants for single-walled carbon nanotubes (SWCNTs). Significant changes in the UV-vis absorption spectra were observed after the formation of the p...
The excited-state dynamics of pyrene incorporated into poly(substituted methylene)s is investigated by picosecond time-resolved fluorescence spectroscopy and femtosecond time-resolved near-IR absorption spectroscopy in the 900-1400 nm region. The ...
B. Narayan   K. Nagura   T. Takaya   K. Iwata   A. Shinohara   H. Shinmori   H. Wang   Q. Li   X. Sun   H. Li   S. Ishihara   T. Nakanishi   
Physical Chemistry Chemical Physics 20(5) 2970-2975 Feb 2018
Novel regioisomeric alkylated-naphthalene liquids were designed and synthesized. In the solvent-free liquid state, 1-alkyloxy regioisomers showed excimeric luminescence, whereas 2-alkyloxy analogues exhibited monomer-rich luminescence features. Co...
Biochimica et Biophysica Acta - General Subjects 1862(2) 335-357 Feb 2018
Novel methodologies utilizing pulsed or intense CW irradiation obtained from lasers have a major impact on biological sciences. In this article, recent development in biophysical researches fully utilizing the laser irradiation is described for th...
PHYSICAL CHEMISTRY CHEMICAL PHYSICS 20(5) 3320-3327 Feb 2018
The electronic and vibrational relaxation of carotenoids is one of the key processes in the protection of living cells as well as in the functions of proteins involved in photosynthesis. In this study, the electronic and vibrational relaxation dyn...
2013 Korea - Japan Symposium on Frontier Photoscience (KJFP-2013), Invited Lecture 50, Hoam Faculty House, Seoul National University, Seoul , Korea 2013