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

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216305%3A26620%2F24%3APU151447" target="_blank" >RIV/00216305:26620/24:PU151447 - isvavai.cz</a>

Result on the web

<a href="https://chemistry-europe.onlinelibrary.wiley.com/doi/10.1002/cptc.202300320" target="_blank" >https://chemistry-europe.onlinelibrary.wiley.com/doi/10.1002/cptc.202300320</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1002/cptc.202300320" target="_blank" >10.1002/cptc.202300320</a>

Result language

angličtina

Original language name

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

Original language description

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.

Czech name

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Czech description

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Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

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OECD FORD branch

10400 - Chemical sciences

Project

—

Continuities

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Publication year

2024

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

ChemPhotoChem

ISSN

2367-0932

e-ISSN

—

Volume of the periodical

8

Issue of the periodical within the volume

7

Country of publishing house

DE - GERMANY

Number of pages

11

Pages from-to

„“-„“

UT code for WoS article

001228234800001

EID of the result in the Scopus database

2-s2.0-85193989779