Issue 2, 2013

Excited-state absorption and ultrafast relaxation dynamics of protoporphyrin IX and hemin

Abstract

The transient evolution of protoporphyrin IX (PPIX) and hemin following the Soret band excitation was measured in the 410–600 nm spectral region with sub-picosecond time resolution. In PPIX the relaxation pathway was characterized in the femto- and picosecond time scale by two processes with time constants of 350 fs and ∼6 ps, describing the evolution of the system through internal Qy → Qx conversion and vibrational relaxation and cooling in the Qx state. The lifetime of the Qx state was found to be 10.4 ns by time resolved fluorescence measurements. In hemin, the ground state is completely recovered in tens of picoseconds through pathways involving CT and (d,d) states. The experimentally observed vibrational dynamics is mainly due to “hot” ground state transitions.

Graphical abstract: Excited-state absorption and ultrafast relaxation dynamics of protoporphyrin IX and hemin

Article information

Article type
Paper
Submitted
09 Jul 2012
Accepted
24 Sep 2012
First published
01 Oct 2012

Photochem. Photobiol. Sci., 2013,12, 348-355

Excited-state absorption and ultrafast relaxation dynamics of protoporphyrin IX and hemin

A. Marcelli, I. Jelovica Badovinac, N. Orlic, P. R. Salvi and C. Gellini, Photochem. Photobiol. Sci., 2013, 12, 348 DOI: 10.1039/C2PP25247C

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Spotlight

Advertisements