Time-resolved energy-dispersive XAS studies of photoinduced electron transfer intermediates in electron donor-acceptor complexes

Lin X. Chen, Peter L. Lee, David Gosztola, Walter A. Svec, Michael R. Wasielewski

Research output: Contribution to journalArticle

11 Citations (Scopus)


The structure around the Fe atom of a photoinduced electron transfer intermediate in a di-porphyrin electron donor/acceptor complex is studied with time-resolved energy dispersive X-ray absorption spectroscopy. Photoinduced electron transfer from the lowest excited triplet state of a Zn porphyrin attached at a fixed 25 D distance by means of a long spacer molecule to an Fe(III) porphyrin occurs with a 6 ms time constant at 77 K. Time domain X-ray absorption measurements show that Fe(III) is transiently photoreduced to Fe(II) and that the bond between the Fe atom and a pyridine molecule ligated to it weakens substantially upon reduction of the Fe. Coupling of ligand loss to reduction of Fe(III) to Fe(II) provides a mean of stabilizing the reduced intermediate.

Original languageEnglish
Pages (from-to)403-405
Number of pages3
JournalJournal of Synchrotron Radiation
Issue number3
Publication statusPublished - May 1 1999



  • Energy dispersive XAS
  • Photoinduced electron transfer
  • Porphyrin complexes
  • Time-resolved XAFS

ASJC Scopus subject areas

  • Radiation
  • Nuclear and High Energy Physics
  • Instrumentation

Cite this