The MathNet Korea
Information Center for Mathematical Science

세미나

Information Center for Mathematical Science

세미나

KAIST 화학과 세미나
Title Enacting Two-Electron Transfer from TT state of Intramolecular Singlet Fission
Date 2019-02-18
Speaker Hyungjun Kim(Incheon National University)
Sponsors 2019-02-18
Host KAIST
Place #3130(E6-4)
Abstract Generating, transferring, and storing multiple electrons from single photons could prove revolutionary for solar energy technologies. One promising process, singlet fission (SF), produces two excited electrons from a single photon.1 This approach could be useful to overcome the theoretical solar cell’s efficiency (Shockley-Queisser limit) and create highly efficient solar cells by reducing thermally wasted high-energy photons. More than one electron needs to be transferred to realize the improvement of photovoltaic cells. In this talk, I will present a simulation-led strategy enacting two-electron transfer between an intramolecular singlet fission chromophore (tetracyanomethylene quinoidal bithiopehene with β,β′-solubilizing groups) and multielectron acceptor (anthraquinone).2 The thermodynamic plausibility of multielectron transfer from a double-triplet state and the absorption spectra of electron transfer (ET) products were predicted using quantum chemical simulations. These predictions are consistent with experimental observations of reduced lifetimes in time-resolved fluorescence spectroscopy, changes in transmission profile, and appearance of new absorption bands in transient absorption spectroscopy, all of which support multi-ET in the QOT2/AQ mixture. The analysis suggests 2ET is favored over 1ET by a 2.5:1 ratio.