000 02677 am a22003733u 4500
042 _adc
100 1 0 _aGillett, Alexander J.
_eauthor
_91393
700 1 0 _aPershin, Anton
_eauthor
_91394
700 1 0 _aPandya, Raj
_eauthor
_91395
700 1 0 _aFeldmann, Sascha
_eauthor
_91396
700 1 0 _aSneyd, Alexander J.
_eauthor
_91397
700 1 0 _aAlvertis, Antonios M.
_eauthor
_91398
700 1 0 _aEvans, Emrys W.
_eauthor
_91399
700 1 0 _aThomas, Tudor H.
_eauthor
_91400
700 1 0 _aCui, Lin-Song
_eauthor
_91401
700 1 0 _aDrummond, Bluebell H.
_eauthor
_91402
700 1 0 _aScholes, Gregory D.
_eauthor
_91403
700 1 0 _aOlivier, Yoann
_eauthor
_91404
700 1 0 _aRao, Akshay
_eauthor
_91405
700 1 0 _aFriend, Richard H.
_eauthor
_91406
700 1 0 _aBeljonne, David
_eauthor
_91407
245 0 0 _aDielectric control of reverse intersystem crossing in thermally activated delayed fluorescence emitters
260 _c2022-10.
500 _a/pmc/articles/PMC7613666/
500 _a/pubmed/35927434
520 _aThermally-activated delayed fluorescence (TADF) enables organic semiconductors with charge transfer (CT)-type excitons to convert dark triplet states into bright singlets via reverse intersystem crossing (rISC). However, thus far the contribution from the dielectric environment has received insufficient attention. Here, we study the role of the dielectric environment in a range of TADF materials with varying changes in dipole moment upon optical excitation. In dipolar emitters, we observe how environmental reorganisation after excitation triggers the full CT exciton formation, minimising the singlet-triplet energy gap, with the emergence of two (reactant-inactive) modes acting as a vibrational fingerprint of the CT product. In contrast, the dielectric environment plays a smaller role in less dipolar materials. The analysis of energy-time trajectories and their free-energy functions reveal that the dielectric environment significantly reduces the activation energy for rISC in dipolar TADF emitters, increasing the rISC rate by three orders of magnitude versus the isolated molecule.
540 _a
540 _ahttps://www.springernature.com/gp/open-research/policies/accepted-manuscript-termsUsers may view, print, copy, and download text and data-mine the content in such documents, for the purposes of academic research, subject always to the full Conditions of use: https://www.springernature.com/gp/open-research/policies/accepted-manuscript-terms
546 _aen
690 _aArticle
655 7 _aText
_2local
786 0 _nNat Mater
856 4 1 _uhttp://dx.doi.org/10.1038/s41563-022-01321-2
_zConnect to this object online.
999 _c800
_d800