相关论文: Intermolecular Vibrations Drive Ultrafast Singlet …
Singlet exciton fission (SF), the conversion of one spin-singlet exciton (S1) into two spin-triplet excitons (T1), could provide a means to overcome the Shockley-Queisser limit in photovoltaics. SF as measured by the decay of S1 has been…
Singlet fission describes the spin-conserving production of two triplet excitons from one singlet exciton. The existence of a spin-2 (quintet) triplet-pair state as a product of singlet fission is well established in the literature, and…
Precise understanding of the electronic structures of optically dark triplet-triplet multiexcitons that are the intermediate states in singlet fission (SF) continues to be a challenge. This is particularly true for intramolecular singlet…
Singlet exciton fission (SEF) is a key process in the development of efficient opto-electronic devices. An aspect that is rarely probed directly, and yet has a tremendous impact on SEF properties, is the nuclear structure and dynamics…
Singlet fission (SF), the spontaneous down-conversion of a singlet exciton into two triplet excitons residing on neighboring molecules, is a promising route to improving organic photovoltaic (OPV) device efficiencies by harvesting two…
The growing interest in harnessing singlet fission for photovoltaic applications stems from the possibility of generating two excitons from a single photon. Quantum efficiencies above unity have been reported, yet the correlation between…
Singlet fission (SF) is a very significant photophysical phenomenon and possesses potential applications. In this work, we try to give the rather detailed theoretical investigation of the SF process in the stacked polyacene dimer by…
We conduct polarization-dependent ultrafast spectroscopy to study the dynamics of singlet fission in tetracene single crystals. The spectrotemporal species for singlet and triplet excitons in transient absorption spectra are found to be…
We report quadruple configuration interaction calculations within the extended Pariser$-$Parr$-$Pople Hamiltonian on the excited states of aggregates of polyenes, crystalline acenes, and covalently linked dimers of acene molecules. We…
Experiments in several intramolecular singlet fission materials have indicated that the triplet-triplet spin biexciton has a much longer lifetime than believed until recently, opening up loss mechanisms that can annihilate the biexciton…
Singlet fission (SF), an exciton multiplication process occurring in organic semiconductors, offers a way to break the Shockley-Queisser limit in single-bandgap photovoltaics (PV). If the triplet excitons generated by SF can be transferred…
Molecular dimers are widely utilized as a tool to investigate the structure-property relationships behind the complex photophysical processes of condensed-phase systems, where structural tuning remains a challenge. This approach often…
We experimentally show that the rate of singlet fission in tetracene films has a superlinear dependence on the density of photo-excited singlet excitons with ultrafast transient absorption spectroscopy. The spectrotemporal features of…
Singlet fission (SF) can potentially break the Shockley-Queisser efficiency limit in single-junction solar cells by splitting one photo-excited singlet exciton (S1) into two triplets (2T1) in organic semiconductors. A dark multi-exciton…
We develop a new first-principles approach to predict and understand rates of singlet fission with an ab initio Green's-function formalism based on many-body perturbation theory. Starting with singlet and triplet excitons computed from a GW…
Spin-entaglement has been proposed and extensively used in the case of correlated triplet pairs which are intermediate states in singlet fission process in select organic semiconductors. Here, we employ quantum process tomography of…
Singlet fission process has gained considerable attention because of its potential to enhance photovoltaic efficiency and break the Shockley Queisser limit. In photovoltaic devices perovskite materials have shown tremendous progress in the…
In this work we study singlet fission in tetracene para-dimers, covalently linked by a phenyl group. In contrast to most previous works, we account for the full quantum dynamics of the combined excitonic and vibrational system. For our…
We investigate the physical mechanisms for spin-dependent recombination of a strongly bound pair of triplet excitons generated by singlet fission and forming a spin quintet (total spin of two) bi-exciton. For triplet excitons the…
We report the first theoretical calculations of excited state absorptions (ESAs) from the singlet and triplet excitons, as well as the key intermediate in the singlet fission (SF) process, the spin singlet multiexciton triplet-triplet…