Detail publikace

Triplet Excited State Mechanistic Study of meso-Substituted Methylthio Bodipy Derivative: Time-Resolved Optical and Electron Paramagnetic Resonance Spectral Studies

Imran, M. Kurganskii, I. Taddei, M. Butera, V. Zhao, JZ. Fedin, MV. Di Donato, M. Mazzone, G.

Originální název

Triplet Excited State Mechanistic Study of meso-Substituted Methylthio Bodipy Derivative: Time-Resolved Optical and Electron Paramagnetic Resonance Spectral Studies

Typ

článek v časopise ve Web of Science, Jimp

Jazyk

angličtina

Originální abstrakt

Understanding the intersystem crossing (ISC) mechanism of organic compounds is essential for designing new triplet photosensitizers. Herein, we investigated the ISC mechanism of a heavy atom-free Bodipy derivative with thiomethyl substitution (S-BDP). A long-lived triplet state was observed with nanosecond transient absorption spectroscopy with lifetime of 7.5 ms in a polymer film and 178 mu s intrinsic lifetime in fluid solution, much longer as compared with what was previously reported (apparent triplet lifetime=15.5 mu s). Femtosecond transient absorption studies retrieved an ISC time constant of similar to 3 ns. Time-resolved electron paramagnetic resonance (TREPR) indicated a special triplet electron spin polarization phase (ESP) pattern (a, e, a, e, a, e) for S-BDP, different from the ESP (e, e, e, a, a, a) typical for the spin-orbital coupling (SOC) mechanism. This indicates that the electron spin selectivity of the ISC of S-BDP is different from that of the normal SOC effect in iodo-Bodipy. Simulations of the TREPR spectra give a zero-field-splitting D parameter of -2257 MHz, much smaller as compared to the reference 2,6-diiodo-Bodipy (D=-4380 MHz). The computed SOC matrix elements (0.28-1.59 cm(-1)) and energy gaps for the S-1/T-n states suggest that the energy matching between the S-1 and T-2/T-3 states (supported by the largest k(ISC) similar to 10(9) s(-1)) enhances the ISC for this compound.

Klíčová slova

BODIPY; intersystem crossing; photosensitizers; time-resolved electron paramagnetic resonance; triplet states

Autoři

Imran, M.; Kurganskii, I.; Taddei, M.; Butera, V.; Zhao, JZ.; Fedin, MV.; Di Donato, M.; Mazzone, G.

Vydáno

1. 7. 2024

Nakladatel

WILEY-V C H VERLAG GMBH

Místo

WEINHEIM

ISSN

2367-0932

Periodikum

ChemPhotoChem

Ročník

8

Číslo

7

Stát

Spolková republika Německo

Strany počet

11

URL

BibTex

@article{BUT188752,
  author="Valeria {Butera} and Muhammad {Imran} and Ivan {Kurganskii} and Maria {Taddei} and Jianzhang {Zhao} and Matvey V. {Fedin} and Mariangela {Di Donato} and Gloria {Mazzone}",
  title="Triplet Excited State Mechanistic Study of meso-Substituted Methylthio Bodipy Derivative: Time-Resolved Optical and Electron Paramagnetic Resonance Spectral Studies",
  journal="ChemPhotoChem",
  year="2024",
  volume="8",
  number="7",
  pages="11",
  doi="10.1002/cptc.202300320",
  issn="2367-0932",
  url="https://chemistry-europe.onlinelibrary.wiley.com/doi/10.1002/cptc.202300320"
}