Time-resolved dynamics of stable open- and closed-shell neutral radical and oxidized tripyrrindione complexes

Byungmoon Cho, Alicia Swain, Ritika Gautam, Elisa Tomat, Vanessa M. Huxter

Research output: Contribution to journalArticlepeer-review

Abstract

Stable open- and closed-shell Pd(ii) and Cu(ii) complexes of hexaethyl tripyrrin-1,14-dione (TD1) produce triplet, doublet or singlet states depending on the metal center and the redox state of the ligand. Pd(ii) and Cu(ii) form neutral TD1 complexes featuring ligand-based radicals, thus resulting in doublet and triplet states, respectively. The reversible one-electron oxidation of the complexes removes an unpaired electron from the ligand, generating singlet and doublet states. The optical properties and time-resolved dynamics of these systems are studied here using steady-state and ultrafast transient absorption (pump-probe) measurements. Fast relaxation with recovery of the ground state in tens of picoseconds is observed for the copper neutral radical and oxidized complexes as well as for the palladium neutral radical complex. Significantly longer timescales are observed for the oxidized palladium complex. The ability to tune the overall spin state of the complexes through their stable open-shell configurations as well as the reversible redox activity of the tripyrrolic systems makes them particularly interesting for catalytic applications as well as exploring magnetism and conductivity properties.

Original languageEnglish (US)
Pages (from-to)15718-15725
Number of pages8
JournalPhysical Chemistry Chemical Physics
Volume24
Issue number26
DOIs
StatePublished - Jun 15 2022

ASJC Scopus subject areas

  • Physics and Astronomy(all)
  • Physical and Theoretical Chemistry

Fingerprint

Dive into the research topics of 'Time-resolved dynamics of stable open- and closed-shell neutral radical and oxidized tripyrrindione complexes'. Together they form a unique fingerprint.

Cite this