Journal of Physical Chemistry Letters
Journal of Physical Chemistry Letters
5 years ago

Vibronic Origin of the Qy Absorption Tail of Bacteriochlorophyll a Verified by Fluorescence Excitation Spectroscopy and Quantum Chemical Simulations

Vibronic Origin of the Qy Absorption Tail of Bacteriochlorophyll a Verified by Fluorescence Excitation Spectroscopy and Quantum Chemical Simulations
Arvi Freiberg, Kristjan Leiger, Juha Matti Linnanto
The long-wavelength tail of the lowest-energy Qy singlet absorption band of bacteriochlorophyll a in triethylamine peaking at 768.6 nm was examined by means of fluorescence excitation spectroscopy at ambient temperature of 22 ± 1 °C. The tail, usually considered a Gaussian, does in fact weaken quasi-exponentially, being clearly evident as far as 940 nm, nearly 2400 cm–1 (∼12 kBT) away from the absorption peak. Quantum chemical simulations identified vibronic transitions from the thermally populated normal modes and their overtones in the ground electronic state as the origin of this tail. Because energy transfer and relaxation processes generally depend on vibronic overlap integrals, these findings may have important implications on the interpretation of numerous photoinduced phenomena that involve bacteriochlorophyll and similar molecules, including photosynthesis.

Publisher URL: http://dx.doi.org/10.1021/acs.jpclett.7b01704

DOI: 10.1021/acs.jpclett.7b01704

You might also like
Discover & Discuss Important Research

Keeping up-to-date with research can feel impossible, with papers being published faster than you'll ever be able to read them. That's where Researcher comes in: we're simplifying discovery and making important discussions happen. With over 19,000 sources, including peer-reviewed journals, preprints, blogs, universities, podcasts and Live events across 10 research areas, you'll never miss what's important to you. It's like social media, but better. Oh, and we should mention - it's free.

  • Download from Google Play
  • Download from App Store
  • Download from AppInChina

Researcher displays publicly available abstracts and doesn’t host any full article content. If the content is open access, we will direct clicks from the abstracts to the publisher website and display the PDF copy on our platform. Clicks to view the full text will be directed to the publisher website, where only users with subscriptions or access through their institution are able to view the full article.