Sulfur rich electron donors – formation of singlet versus triplet radical ion pair states featuring different lifetimes in the same conjugate

Saha, Avishek; Chen, Muqing; Lederer, Marcus; Kahnt, Axel; Lu, Xing; Guldi, Dirk M.

doi:10.1039/c6sc03207a

Cited by 12 publications

(9 citation statements)

References 45 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Such pathways have been well documented previously. [43][44][45][46][47][48] Generally, a small r DA , as observed in our system <$5 Å , makes the energy difference (or electronic coupling) between 1 CS and 3 CS sufficiently large so that the RP-ISC, which typically occurs through a weak hyperfine coupling ($10 7 -10 8 s À1 ), does not readily occur and only incoherent relaxation ($10 6 s À1 ) 49 occurs in the absence of external magnetic fields. 46,50,51 We further confirmed a lack of MFEs on the formation of triplets by conducting ns-TA in the presence of external magnetic field up to 3,000 gauss (Figure S13).…”

Section: Discussion Efficient Charge Separation In Orthogonal D-a Bodipy Pairmentioning

confidence: 57%

Spin-Allowed Transitions Control the Formation of Triplet Excited States in Orthogonal Donor-Acceptor Dyads

Buck

Boudreau

DeCarmine

et al. 2019

Chem

103

181

View full text Add to dashboard Cite

Triplet excited states (triplets) serve as key intermediates in critical technologies and processes ranging from organic synthesis to biomedicine to molecular electronics. Production of triplets of p-conjugated organic molecules without heavy atoms remains challenging. Spin-orbit, charge-transfer intersystem crossing (SOCT-ISC) directly converts singlet charge-separated states to triplets in an electron donor-acceptor (D-A) pair. Here, using a series of orthogonal D-A type boron dipyrromethene (BODIPY) derivatives as a model system, we show that the formation of triplets is largely controlled by the spin-allowed transitions rather than by SOCT-ISC. Yet, the SOCT-ISC process can still proceed much faster than ordinary ISC between (p, p*) states because the spin-orbit coupling of SOCT-ISC is 2 orders of magnitude stronger. We further show that such a process can produce triplets in a non-triplet-forming molecule, perylene. Our findings reveal a clear physical basis for this spin-forbidden process and provide guidelines for future molecular designs exploiting the process.

show abstract

Section: Discussion Efficient Charge Separation In Orthogonal D-a Bodipy Pairmentioning

confidence: 57%

Spin-Allowed Transitions Control the Formation of Triplet Excited States in Orthogonal Donor-Acceptor Dyads

Buck

Boudreau

DeCarmine

et al. 2019

Chem

103

181

View full text Add to dashboard Cite

show abstract

“…Radical formation was investigated by two methods: electrochemical oxidation and UV-irradiation. Both of these methods can generate radical cations in TPA compounds, with the former being well-known,8 and the latter requiring a reducible agent in the molecule itself18 or in molecules close-by ( i.e. solvent) 19.…”

Section: Introductionmentioning

confidence: 99%

UV-irradiation of self-assembled triphenylamines affords persistent and regenerable radicals

et al. 2019

View full text Add to dashboard Cite

show abstract

“…This mechanism may explain the phenomenon of aggregation/ assembly induced energy transfer from carbon quantum dots to Europium(III) because rigid microrods are in favor of the orbital overlap (bond) between CQDs and Eu (III) ions, and the sulfur elements in CQDs would facilitate the efficient intersystem crossing into triplet states. 39,40 Sensing Ability of CQDs-Eu (III) Microrods for Pi. In order to detect Pi in fingerprint, the fluorescence response of the dual-emission microrods toward Pi with various concentrations is studied and depicted in Figure 2.…”

Section: ■ Results and Discussionmentioning

confidence: 99%

“…These results indicate the importance of spectral overlap and the bond between CQDs and Eu (III) to the energy transfer and excitation of Eu (III) by CQDs should be attributed to Dexter process. This mechanism may explain the phenomenon of aggregation/assembly induced energy transfer from carbon quantum dots to Europium(III) because rigid microrods are in favor of the orbital overlap (bond) between CQDs and Eu (III) ions, and the sulfur elements in CQDs would facilitate the efficient intersystem crossing into triplet states. , …”

Section: Resultsmentioning

confidence: 99%

Carbon Quantum Dots–Europium(III) Energy Transfer Architecture Embedded in Electrospun Nanofibrous Membranes for Fingerprint Security and Document Counterspy

Liu

Yang

et al. 2019

Anal. Chem.

View full text Add to dashboard Cite

Traditional fingerprints are usually obtained by pressing an inked finger on a paper. The inks would contaminate fingers and more importantly, these fingerprints are visible and able to be photocopied. In order to develop a smart membrane for fingerprint recording and document security, microrod assemblies of carbon quantum dots (CQDs)-Eu (III) are embedded in a electrospun nanofibrous (NFs) membrane which has strong red emission under UV irradiation owing to aggregation induced Dexter energy transfer from CQDs to Eu (III) ions. A clear blue emission fingerprint could be recorded on the membrane after a finger touch because the phosphate (Pi) secreted through sweat glands blocks the solid-state Dexter energy transfer, recovering the UVirradiated blue emissions of CQDs. The Pi-based fingerprint on the membrane, which is invisible under daylight and could not be photocopied, greatly improves the security of the fingerprint and, furthermore, has the capability to identify the people who touched the secret document through the fingerprint analysis, showing that the intelligent NFs membrane can be applied for both fingerprint security and document counterspy.

show abstract

Sulfur rich electron donors – formation of singlet versus triplet radical ion pair states featuring different lifetimes in the same conjugate

Abstract: An unprecedented family of novel electron-donor acceptor conjugates based on fullerenes have been synthesized and characterized in a variety of solvents.

Cited by 12 publications

References 45 publications

Spin-Allowed Transitions Control the Formation of Triplet Excited States in Orthogonal Donor-Acceptor Dyads

Spin-Allowed Transitions Control the Formation of Triplet Excited States in Orthogonal Donor-Acceptor Dyads

UV-irradiation of self-assembled triphenylamines affords persistent and regenerable radicals

Carbon Quantum Dots–Europium(III) Energy Transfer Architecture Embedded in Electrospun Nanofibrous Membranes for Fingerprint Security and Document Counterspy

Contact Info

Product

Resources

About