...and the link to the paper:
doi.org/10.1063/5.03...

Matthias' paper with a thorough investigation of a Coulombic Dyad has been published in Chem. Phys. Rev. as a part of the "70 Years of Dexter Energy Transfer" collection. Many thanks also to our collaborators from the @labheinze.bsky.social and Diezemann groups). #Photochemistry #EnergyTransfer

Exploring Spin-State Selective Harvesting Pathways from Singlet Fission Dimers to a Near-Infrared-Emissive Spin-Flip Emitter Singlet fission (SF), a photophysical process generating two triplet excitons from one singlet exciton, has the potential to boost efficiency in photovoltaics and organic light-emitting diodes. Previous studies on energy-level control and intermolecular interactions have identified key factors for maximizing the efficiency of the initial SF process. However, in isothermic/endothermic SF systems, such as tetracene derivatives, the subsequent sensitization process becomes less efficient in the presence of a competing Förster resonance energy transfer (FRET) process. Here, we demonstrate that a molybdenum-based near-infrared light-emitting spin-flip emitter serves as a triplet-selective energy acceptor from triplet states of tetracene-based dimers generated by SF. The large energy gap existing between the spin-allowed transitions and the luminescent spin-flip transition of the molybdenum complex allowed efficient exothermic triplet energy transfer (TET) to the spin-flip excited doublet state of the complex while circumventing the FRET from the initially formed tetracene singlet state to the high-energy spin-allowed states of the complex. The quantum yields of the doublet state formation of the molybdenum complex by tetracene-based SF dimers with phenylene, 2,5-methylphenylene, and p-terphenylene bridging units were quantified to be 112 ± 6%, 132 ± 2%, and 128 ± 4%, respectively, in solution. The drop of fluorescence lifetimes of the SF dimers at high concentrations of the molybdenum complex implies energy transfer from exchange-coupled triplet pairs, highlighting the importance of controlling exchange interaction and triplet pair recombination. This work represents a significant step toward developing exciton/photon amplification materials by combining SF materials with transition-metal complexes, advancing the application of SF beyond conventional limitations.

Exploring Spin-State Selective Harvesting Pathways from Singlet Fission Dimers to a Near-Infrared-Emissive Spin-Flip Emitter | Journal of the American Chemical Society pubs.acs.org/doi/10.1021/...

Photochemical Cyclization of Tertiary Buta‐2,3‐dienamides to β‐Lactams Upon Triplet Energy Transfer Energy transfer is the key to the successful photocyclization of the title compounds to 3,4-disubstituted 2-azetidinones. If the substituent at the nitrogen atom is primary (R2 = H), trans products a...

We're very proud to announce our newest publications on the photochemical cyclization of tertiary buta-2,3-dienamides to β-lactams! A big thanks to the collaborators from the Kerzig Group (@ckerzig.bsky.social) @angewandtechemie.bsky.social #photochemistry 💡🙌🧑‍🔬
onlinelibrary.wiley.com/doi/10.1002/...

Molecular Solar Thermal (MOST) Energy Storage—Definitions and Requirements Revisited Molecular solar thermal storage (MOST) systems have recently regained great interest after a period of intense research around five decades ago. This perspective clarifies the nomenclature, and intro...

New perspective out! We revisit the foundations of molecular solar thermal storage (MOST) and introduce the term „mostophore“ to describe molecular units that harvest and store solar energy as heat. ☀️ Moreover, we highlight key directions for future solar-energy research.

doi.org/10.1002/anie...

The symposium will start in about 2 hours. Don't miss the opportunity to hear five short talks dealing with diverse topics in the #photochemistry field, followed by a plenary lecture. 👇

On my way to Basel to attend the Dreyfus Lectureship, which will be given by Jim McCusker. Sun is shining and the train is almost on time. #MondayMorning

The first online symposium organized by the @gdch.de Division of Photochemistry will take place next week (Nov. 5, 2025, 3 pm CET zone).
tu-braunschweig.webex.com/tu-braunschw...
key: Photo2025
5 talks by talented students (one will be awarded🎉) followed by a plenary lecture. Save the date. ✍️

Nice piece of work Kasper & team. I guess we should update this sentence in our current preprint: "While the influence of TIPS-ethynyl groups was not investigated with the frequently-studied perylene annihilator chromophore, ..."😅

Till defended his PhD thesis today.🍾 Extremely convincing discussion and great performance resulted in degree with highest distinction💪. All the best for your postdoc in Bologna, where Giacomo Ciamician did pioneering work in #photochemistry. Curious to see what Till will achieve 🤔

Julian's manuscript dealing with a novel biphenyl annihilator and unusual effects of different substituents. Is it a new benchmark system for blue-to-UV upconversion? Read about it here: chemrxiv.org/engage/chemr...
Many thanks to our collaboration partner @nobuhiroyanai.bsky.social and Masanori.

Manganese edges into the realm of noble-metal photochemistry Pairing manganese with an off-the-shelf ligand yields a low-cost complex that mimics precious-metal photocatalysts

Researchers at Johannes Gutenberg University Mainz report a manganese complex that stays energized for 190 ns after absorbing light—a record for low-cost abundant metals. cen.acs.org/materials/in... #chemsky 🧪

Is it allowed in Germany to advertise a position for female candidates only (according to the "Allgemeines Gleichbehandlungsgesetz" (AGG))?

Photoinduced double charge accumulation in a molecular compound - Nature Chemistry The photoinduced accumulation of redox equivalents is a challenging requirement for artificial photosynthesis. Now a molecule has been developed in which the sequential absorption of photons results i...

New molecular design absorbs 2 photons to store 2 positive and 2 negative charges

100 ns lifetime, 3 eV energy storage, and 37% quantum yield

A step toward multi-electron photochemistry

Mathis Brändlin and @bjoernpfund.bsky.social in @natchem.nature.com

www.nature.com/articles/s41...

All of your favorite metals included?

Breaking Kasha’s Rule to Enable Higher Reactivity in Photoredox Catalysis Nearly all photochemical transformations known to date follow Kasha’s rule, implying that reactions occur only from the lowest electronically excited state of a given spin multiplicity due to the fast...

We show how photoredox catalysis can bypass Kasha’s rule, enabling reactions from higher excited states.

This work, led by the exceptional @bjoernpfund.bsky.social, offers new insights into photochemical reactivity.

Published in JACS @jacs.acspublications.org

bit.ly/3IysmjX

The next masterpiece from Matthias focusing on Coulombic dyads as new #photocatalyst class has been accepted in ACIE. Higher quantum yields in red-light catalysis by adding an inexpensive salt to use #Os as efficiently as possible. onlinelibrary.wiley.com/doi/10.1002/... @labheinze.bsky.social

Two weeks left for completing the registration for the Molecules and Light 2025 conference in beautiful Poznań. Also abstract submission is still possible.
molecules_light2025.web.amu.edu.pl

Pushing the limit of triplet–triplet annihilation photon upconversion towards the UVC range Triplet–triplet annihilation photon upconversion (TTA-UC) provides a milder alternative to traditional UVB/UVC photochemistry. However, suitable sensitizer-annihilator pairs are scarce, in particular…

New Hot article from @ckerzig.bsky.social, @gloriusfrank.bsky.social and colleagues:

'Pushing the limit of triplet–triplet annihilation photon upconversion towards the UVC range' 🔥

#OpenAccess 🔓

One photon or two photons, that is the question. We discuss mechanistic challenges, pitfalls, and opportunities for future research in two-photon photocatalysis @angewandtechemie.bsky.social. Many thanks to first-authors Julian and Sophie.

onlinelibrary.wiley.com/doi/10.1002/...

Direct Observation of Triplet–Triplet Energy Transfer in DNA between Energy Donor and Acceptor C-Nucleotides Investigating the migration of excited-state energy in DNA is crucial for a deep understanding of protection mechanisms and light-induced DNA damage. While numerous reports focused on single electron transfer and Förster-type energy transfer in DNA, studies on the Dexter-type triplet–triplet energy transfer are scarce, in particular, those with direct detection of photoexcited triplet states. Herein, we present direct measurements of the distance-dependent triplet–triplet energy transfer rates through DNA by using transient absorption spectroscopy. This was achieved through the synthetic incorporation of thioxanthone as an energy donor and naphthalene as an energy acceptor into a DNA double strand at defined positions. The energy transfer rates strongly depend on the number of A-T base pairs (up to four) separating the energy donor from the energy acceptor. We observed a fast energy transfer rate with a time constant of 17 ns for the DNA sample in which the donor and acceptor are directly adjacent in the DNA. By analyzing two additional donor–acceptor distances, a steep exponential distance dependence with an attenuation factor of 1.15 Å–1 could be obtained. Our results demonstrate that DNA acts as a poor conductor of triplet energy when energy donors with triplet energies below 2.7 eV are used, complementing more indirect studies on sensitized DNA damage.

The last paper of Till's PhD has finally been accepted and is online in JACS Au
pubs.acs.org/doi/10.1021/...
Insights into energy transfer in DNA through a fruitful collaboration with the Wagenknecht lab.

Sie sind Vorbilder für Nachwuchswissenschaftler:innen und prägen durch ihren herausragenden Einsatz in Forschung & Entwicklung den Innovationsstandort 🇩🇪 entscheidend mit: unsere Dozentenpreisträger:innen Corina Andronescu, @ckerzig.bsky.social & Golo Storch! www.vci.de/fonds/preise...

It was our pleasure. We really enjoyed working with the user-friendly instrument. Many thanks for developing the HARPIA-LIGHT system. Here is the link to the first paper containing measurements carried out with it: pubs.acs.org/doi/10.1021/...

Can you #recyle your molecular #photocatalyst? Can you use #water in your #photocatalysis? Can you use #sunlight? Can undergrads prepare the photocatalyst on >12 g scale? Out now in Advanced Synthesis and Catalysis lmy.de/BgahY. Thanks to @dfg.de for funding.

Many thanks for your kind words. Highly appreciated!
It was also great to interact with you during the coffee break.

Our collaborative manuscript with the Wagenknecht lab (KIT) is finally online. Dexter energy transfer in DNA and its distance dependence has been observed using TA spectroscopy. #triplet #photochemistry

Our very own Matthias after presenting his results on Coulombic dyads. pubs.acs.org/doi/10.1021/...
#proudPI #photochemistry

One month to go to the abstract submission deadline (24/03/25) for contributed talks at the 5th International #SolarFuels conference, which we're organising together with the @rsc.org in Newcastle, UK, this September.

#chemsky #photocatalysis

Danke Max

Vielen Dank, Mathias 😀