1994 Fiscal Year Final Research Report Summary
Fractal Structures and Excitation Energy Relaxation in Molecular Assemblies
| Project/Area Number |
03403001
|
|---|
| Research Category |
Grant-in-Aid for General Scientific Research (A)
|
| Allocation Type | Single-year Grants |
|---|
| Research Field |
物理化学一般
|
|---|
| Research Institution | Hokkaido University, Faculty of Science |
|---|
Principal Investigator |
YAMAZAKI Iwao Hokkaido Univ.Faculty of Engineering, Professor, 工学部, 教授 (80002111)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
AKIMOTO Seiji Hokkaido Univ.Faculty of Engineering, Research Associate, 工学部, 助手 (40250477)
NISHIMURA Yosinobu Hokkaido Univ.Faculty of Engineering, Research Associate, 工学部, 助手 (60218211)
OHTA Nobuhiro Hokkaido Univ.Faculty of Engineering, Associate Professor, 工学部, 助教授 (70113529)
|
|---|
| Project Period (FY) |
1991 – 1994
|
| Keywords | Fractal / LB films / Hydrophobic polymers / Picosecond laser / Energy transfer / Fluorescence decays / Polymer colloids / Phase transition |
|---|
| Research Abstract |
Organic molecules in general form self-assembled organizates. Typical examples are vesicles, Langmuir-Blodgett (LB) monolayr films and liquid crystals, in which some structural orders appear with respect to molecular orientation and spatial distribution of guest molecules, and determine the macroscopic morphology of these assemblies. In this study, the structural orders have been investigated by means of the excitation energy transfer between molecules monitored with a picosecond time-resolved fluorescence spectroscopy. The spatial distribution of molecules, which can be expressed in terms of "fractal", was investigated for polymers and LB films. It was found that the fractal dimension depends on (d) types of molecules, molecular inteaction : d = 1.7 in a surface of silicagel microcrystals, d = 1.3 - 1.7 in LB films of cyanine and rhodamine dyes, and d = 1.0 - 1.4 in hydrophobic plymers. The dynamical properties of excitation energy relaxation are characterized by the energy hopping migration among sites of slightly different energies.
|
