Real-time observation of intersystem crossing induced by charge recombination during bimolecular electron transfer reactions
AuthorsAlsam, Amani A.
Aly, Shawkat Mohammede
Parida, Manas R.
Mohammed, Omar F.
KAUST DepartmentChemical Science Program
KAUST Catalysis Center (KCC)
KAUST Solar Center (KSC)
Physical Sciences and Engineering (PSE) Division
Online Publication Date2016-09-21
Print Publication Date2017-01
Permanent link to this recordhttp://hdl.handle.net/10754/622240
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AbstractReal-time probing of intersystem crossing (ISC) and triplet-state formation after photoinduced electron transfer (ET) is a particularly challenging task that can be achieved by time-resolved spectroscopy with broadband capability. Here, we examine the mechanism of charge separation (CS), charge recombination (CR) and ISC of bimolecular photoinduced electron transfer (PET) between poly[(9,9-di(3,3′-N,N’-trimethyl-ammonium) propyl fluorenyl-2,7-diyl)-alt-co-(9,9-dioctyl-fluorenyl-2,7-diyl)] diiodide salt (PFN) and dicyanobenzene (DCB) using time-resolved spectroscopy. PET from PFN to DCB is confirmed by monitoring the transient absorption (TA) and infrared spectroscopic signatures for the radical ion pair (DCB─•-PFN+•). In addition, our time-resolved results clearly demonstrate that CS takes place within picoseconds followed by CR within nanoseconds. The ns-TA data exhibit the clear spectroscopic signature of PFN triplet-triplet absorption, induced by the CR of the radical ion pairs (DCB─•-PFN+•). As a result, the triplet state of PFN (3PFN*) forms and subsequently, the ground singlet state is replenished within microseconds. © 2016
CitationAlsam AA, Aly SM, Parida MR, Alarousu E, Cao Z, et al. (2017) Real-time observation of intersystem crossing induced by charge recombination during bimolecular electron transfer reactions. Dyes and Pigments 136: 881–886. Available: http://dx.doi.org/10.1016/j.dyepig.2016.09.049.
SponsorsThis work was supported by King Abdullah University of Science and Technology (KAUST). This work is also supported by Saudi Arabia Basic Industries Corporation (SABIC) grant RGC/3/2470-01.
JournalDyes and Pigments