電子励起緩和過程を支配する熱平衡分布と活性化エネルギーの物理化学的意味

1995 Fiscal Year Final Research Report Summary

• Project/Area Number: 06453024
• Research Category: Grant-in-Aid for General Scientific Research (B)
• Allocation Type: Single-year Grants
• Research Field: Physical chemistry
• Research Institution: Kyoto Institute of Technology
• Principal Investigator: HIRAYAMA Satoshi KIT,Professor, 繊維学部, 教授 (90027912)
• Co-Investigator(Kenkyū-buntansha): TANAKA Fujio Uni.Osaka Prof.lecturer, 総合科学部, 講師 (60109874)
• Project Period (FY): 1994 – 1995
• Keywords: 9-cyanoanthracene / Activation energy / van der Waals complexes / Supersonic free jet / Thermal activation / Partially cooled states / Dark states / Laser free spectroscopic measurements

Research Abstract

We have successfully developed a simple but powerful technique by which the absorption and fluorescence excitation spectra of isolated or van der Waals complexes generated in supersonic jets can be measured simultaneously.The technique, which dispenses with any laser and is achieved for the first time in the world (Rev.Sci.Instrum., in press), will allow one to explore a new field of molecular relaxation dynamics, in particular, in which dark states or non-emissive levels play a decisive role.
Intensive studies have been carried out on the following four subjects by using the developed technique. We have obtained extremely exciting results on each subject.
1.State selective relaxation processes and thermal activation. We have already submitted a paper entitled "Thermal energy assisted heavy atom effect-Fluorescence quenching of 9-cyanoanthracene in supercritical fluid of Xe".
2.Fluorescence quenching of anthracene derivatives and van der Waals complex formation with oxygen.
3.Non-radiative processes of non-fluorescent anthracenes.
4.Electronic relaxation processes from partially cooled states (PCS). The idea of PCS was introduced by us many years ago. The present technique is found to provide us novel information about PCS.

Research Products

• [Publications] F. TANAKA,et al.: "Effects of clustering of rare-gas atoms on the rate of S_1-T_2 intersystem crossing for 9-methylanthracene" Chemical Physics Letters. (in press). (1996)
  • Description: 「研究成果報告書概要(和文)」より
• [Publications] U. GRAF,et al.: "Laser-free measurements of absorption and fluorescence excitation spectra in a supersonic free jet" Rev. Sci. Instrum.(in press). (1996)
  • Description: 「研究成果報告書概要(和文)」より
• [Publications] F. TANAKA,et al.: "Pressure and temperature dependences of the rate constant for S_1-T_2 intersystem crossing of anthracene compounds in solution" J. Phys. Chem.99. 525-530 (1995)
  • Description: 「研究成果報告書概要(和文)」より
• [Publications] S. HIRAYAMA,et al.: "Energy and state selective electronic relaxation of anthracene derivatives and their van der Waals complexes-An attempt to link dynamics in gas phase and solution" Trends in photochemistry & Photobiology. 3. 549-579 (1994)
  • Description: 「研究成果報告書概要(和文)」より
• [Publications] F.TANAKA et al.: "Effects of clustering of rare-gas atoms on the rate of S_1-T_2 intersystem crossing for 9-methylanthracene" Chemical Physics Letters. (in press).
  • Description: 「研究成果報告書概要(欧文)」より
• [Publications] U.GRAF et al.: "Laser-free measurements of absorption and fluorescence excitation spectra in a supersonic free jet" Rev.Sci.Instrum.(in press).
  • Description: 「研究成果報告書概要(欧文)」より
• [Publications] F.TANAKA et al.: "Pressure and temperature dependences of the rate constant for S_1-T_2 intersystem crossing of anthracene compounds in solution" J.Phys.Chem.99. 525-530 (1995)
  • Description: 「研究成果報告書概要(欧文)」より
• [Publications] S.HIRAYAMA et al.: "Energy and state selective electronic relaxation of anthracene derivatives and their van der Waals complexes-An attempt to link dynamics in gas phase and solution" Trends in Photochemistry & Photobiology. 3. 549-579 (1994)
  • Description: 「研究成果報告書概要(欧文)」より