2001 Fiscal Year Final Research Report Summary
Coherent Photochemical Reactions in Sequential Molecular Systems-Measurement and Theoretical Formulation
| Project/Area Number |
11223203
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research on Priority Areas (B)
|
| Allocation Type | Single-year Grants |
|---|
| Review Section |
Science and Engineering
|
|---|
| Research Institution | HOKKAIDO UNIVERSITY |
|---|
Principal Investigator |
YAMAZAKI Iwao Hokkaido Univ., Grad., School of Eng., Prof., 大学院・工学研究科, 教授 (80002111)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
SATO Shin-ichiro Hokkaido Univ., Grad. School of Eng., Assoc. Prof., 大学院・工学研究科, 助教授 (10262601)
OHTA Nobuhiro Hokkaido Univ., Res. Inst. Electronic Sci., Prof., 電子科学研究所, 教授 (70113529)
SUMI Hitoshi Univ. Tsukuba., Inst. of Materials Science, Prof., 大学院・物質工学系, 教授 (10134206)
AKIMOTO Seiji Hokkaido Univ., Grad. School of Eng., Inst., 大学院・工学研究科, 助手 (40250477)
NISHIMURA Yoshinobu Hokkaido Univ., Grad. School of Eng., Inst., 大学院・工学研究科, 助手 (60218211)
|
|---|
| Project Period (FY) |
1999 – 2001
|
| Keywords | Molecular assemblies / Coherent reaction / Supramolecules / Femtosecond fluorescence / Quantum interference / Photosynthesis |
|---|
| Research Abstract |
The Coherent nature of photochemical reaction has been established for highly organized molecular systems through the experimental mesurement and theoretical formulation. The results are summarized as follows.
(1) The first observation of quantum beat signal has been attained for cyclic motion of exciton between two chromophores inanthracene dimers and perylene dimers. This means that the exciton moves coherently back and forth between the two chromophores, and that the photochemical reaction in molecular systems occurs coherently in several ps before the electronic decoherence. A special apparatus was constructed which was capable of quantum-interference control of the reaction.
(2) The coherent photochemical reaction under external electric field was investigated, and found that the reaction was controlled by applying electric field. Several types of porphyrin arrays of 1D (Osuka compounds) exhibited a significant enhancement of conductivity upon photoexcitation. These molecular systems may function as molecular wires switchable by photo-irradiation.
(3) The theoretical formulation has been established for coherent transports of electron and exciton in photosynthetic reaction centers (RC) in plants A higher-order perturbation theory was applied to the cyclic and sequential arrangements of molecules inside the RC proteins.
In Summary, the present reserch project has attained 90% success for the reserch program that we planned initially.
|
