Time-resolved resonance Raman spectra of chlorophyll a in the lowest excited triplet state: Effect of the state of coordination

✍ Scribed by Masayuki Kanzaki; Tetsuro Yuzawa; Hidefumi Hiura; Hiroaki Takahashi

• Publisher: Elsevier Science
• Year: 1990
• Tongue: English
• Weight: 299 KB
• Volume: 169
• Category: Article
• ISSN: 0009-2614
• DOI: 10.1016/0009-2614(90)85170-h

✦ Synopsis

Resonance Raman spectra of the lowest excited triplet state of chlorophyll a are obtained in benzene and in methanol by pumping at 660 nm in the Q, band and pmbing at 460 nm which is close to the absorption maximum of the T, state. Tbe spectrum observed in polar methanol differs significantly from that observed in benzene. In particular, the bands in the 161 O-1500 cm-' region arc found to be downshifted on going fmm benzene to methanol solutions. The downshifts are attributed to the difference in the state of coordination of the Mg atom and possibly to the difference in the state of aggregation in the two solvents: pentacoordinated and aggregated in benzene versus predominantly hexacoordinated and monomeric in methanol