TY - JOUR
T1 - Thermodynamic equilibrium between locally excited and charge-transfer states through thermally activated charge transfer in 1-(pyren-2′-yl)-o-carborane
AU - Ji, Lei
AU - Riese, Stefan
AU - Schmiedel, Alexander
AU - Holzapfel, Marco
AU - Fest, Maximillian
AU - Nitsch, Jörn
AU - Curchod, Basile F.E.
AU - Friedrich, Alexandra
AU - Wu, Lin
AU - Al Mamari, Hamad H.
AU - Hammer, Sebastian
AU - Pflaum, Jens
AU - Fox, Mark A.
AU - Tozer, David J.
AU - Finze, Maik
AU - Lambert, Christoph
AU - Marder, Todd B.
N1 - Publisher Copyright:
© 2022 The Royal Society of Chemistry.
PY - 2022/1/1
Y1 - 2022/1/1
N2 - Reversible conversion between excited-states plays an important role in many photophysical phenomena. Using 1-(pyren-2′-yl)-o-carborane as a model, we studied the photoinduced reversible charge-transfer (CT) process and the thermodynamic equilibrium between the locally-excited (LE) state and CT state, by combining steady state, time-resolved, and temperature-dependent fluorescence spectroscopy, fs- and ns-transient absorption, and DFT and LR-TDDFT calculations. Our results show that the energy gaps and energy barriers between the LE, CT, and a non-emissive ‘mixed’ state of 1-(pyren-2′-yl)-o-carborane are very small, and all three excited states are accessible at room temperature. The internal-conversion and reverse internal-conversion between LE and CT states are significantly faster than the radiative decay, and the two states have the same lifetimes and are in thermodynamic equilibrium.
AB - Reversible conversion between excited-states plays an important role in many photophysical phenomena. Using 1-(pyren-2′-yl)-o-carborane as a model, we studied the photoinduced reversible charge-transfer (CT) process and the thermodynamic equilibrium between the locally-excited (LE) state and CT state, by combining steady state, time-resolved, and temperature-dependent fluorescence spectroscopy, fs- and ns-transient absorption, and DFT and LR-TDDFT calculations. Our results show that the energy gaps and energy barriers between the LE, CT, and a non-emissive ‘mixed’ state of 1-(pyren-2′-yl)-o-carborane are very small, and all three excited states are accessible at room temperature. The internal-conversion and reverse internal-conversion between LE and CT states are significantly faster than the radiative decay, and the two states have the same lifetimes and are in thermodynamic equilibrium.
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UR - https://www.mendeley.com/catalogue/1f5e8efa-dde5-3eaf-b85b-827bf35d566f/
U2 - 10.1039/d1sc06867a
DO - 10.1039/d1sc06867a
M3 - Article
C2 - 35655553
AN - SCOPUS:85129865587
SN - 2041-6520
VL - 13
SP - 5205
EP - 5219
JO - Chemical Science
JF - Chemical Science
IS - 18
ER -