Alejandro Cadranel

Stimuli-Responsive Thiele’s Hydrocarbon Derivatives: Potential Inversion, Strong Electronic Coupling, and Influence of Brønsted/Lewis Acids and Bases Stimuli-responsive diradicaloid systems often display fascinating and tunable electrochemical, optical, and magnetic properties. Herein, we present the design and synthesis of a series of nitrogen-con...

Finally out! Very happy about this work with Alok Mahata, Biprajit Sarkar et al.!!
#chemsky #science #compchem

Stimuli-Responsive Thiele’s Hydrocarbon Derivatives: Potential Inversion, Strong Electronic Coupling, and Influence of Brønsted/Lewis Acids and Bases | JACS Au pubs.acs.org/doi/10.1021/...

Red-Light Photoredox C–H Alkylation Enabled by Catalytic NADH, now out in @chemrxivbot.bsky.social

chemrxiv.org/doi/full/10....

From synthetic application to TAS mechanistic understanding, passing through radical biocompatibility.

Awesome collab @ciqus.bsky.social and @cadralab.bsky.social

Beyond the Diffusion Limit: Preassociation Enhanced Photon Upconversion and Photocatalysis Sensitized by Iron Complex Photoactive iron complexes present highly desirable and accessible alternatives to the well-known noble metal complex-based photocatalysts, thanks to iron’s high abundance, low toxicity, and minimal e...

Excited to share another first-author paper from Pengyue Jin: Beyond the Diffusion Limit: Preassociation Enhanced Photon Upconversion and Photocatalysis Sensitized by Iron Complex | ACS Catalysis
Great thanks to the @dfg.de for the funding!
pubs.acs.org/doi/full/10....

Expanding Thermodynamic and Kinetic Frontiers in Molecular Photocatalysis Visible photons carry significantly more energy than the thermal energies typically used to overcome activation barriers in conventional chemistry. This thermodynamic advantage enables photochemical reactions that are inaccessible from electronic ground states. However, photochemistry also faces a kinetic challenge: excited states are inherently short-lived, necessitating rapid reactivity before their decay. In this Outlook, we explore the unique interplay of thermodynamics and kinetics in molecular photochemistry. We highlight current limits and knowledge gaps and propose directions for advancing the conceptual framework of photocatalysis. Topics include the design of photocatalysts with extreme redox potentials, the use of solvated electrons and visible-to-UV upconversion, and the potential to bypass Kasha’s rule for higher-energy photochemical processes. Our aim is to survey strategies for pushing the boundaries of photocatalysis and to inspire future conceptual innovation in the field.

Expanding Thermodynamic and Kinetic Frontiers in Molecular Photocatalysis

Extreme redox potentials, solvated electrons, upconversion, ultrafast photo-dissociation, slow uphill reactions and beyond

@pubs.acs.org

pubs.acs.org/doi/10.1021/...

Our work on photocatalytic carbon dots was featured in the Editor's Highlights collection! Check it out in the "Materials Science and Chemistry" section

www.nature.com/ncomms/edito...

Synthesis and Excited-State Dynamics in Molecular Nanographene: Herzberg–Teller Vibronic Coupling and Energy Transfer to Porphyrins Nanographenes (NGs) and graphene nanoribbons (GNRs) are molecular-level bridges to bulk-carbon materials. When synthesized with atomic precision via, for example, bottom-up strategies, a direct connection between the structure and properties is demonstrable. This is of key interest, especially considering practical applications. In the current work, we report the synthesis and comprehensive photophysical characterization of a full-benzenoid nanographene (NG-Br) and its covalent conjugate featuring a porphyrin (NG-(Zn)Por). Our synthetic approach relies on a cascade of Suzuki coupling, reduction, and Sandmeyer bromination reactions, starting from halogenated nitrobenzene derivatives. Knowing at which concentration aggregation occurs is important to study either monomers of NG-Br or its aggregates. In organic solvents, the association constant of NG-Br exceeds 1 × 106 M–1. Photophysical and theoretical analyses on the monomer revealed a subtle energy proximity between (S1)/(Lb) and (S2)/(La) that is the basis for strong vibronic coupling via the Herzberg–Teller mechanism, as well as (S1,1) and (S2,0) vibronic mixing. In NG-(Zn)Por, an ultrafast (S1–S1) energy transfer from NG to the porphyrin was observed. Our findings are essential for establishing an unambiguous structure–property relationship for NGs and 9-armchair GNRs, providing a blueprint for their use in optoelectronic devices ranging from single-electron transistors to OLEDs and organic solar cells.

➡️ Increasing the length of molecular nanographenes leads to higher photoluminescence quantum yields!💡

In this @jacs.acspublications.org paper, we show how molecular length tunes the interplay between dark and bright excited states.

🔗 pubs.acs.org/doi/10.1021/...

Many thanks to all coauthors!!

Enzyme-inspired single-atom photocatalysis for oxygen reduction to hydrogen peroxide Nature Communications - Selective conversion of oxygen into hydrogen peroxide under light irradiation was achieved using enzyme-inspired carbon dots decorated with single copper ions. Time-resolved...

Very happy to see this massive 3-yr effort out
@natcomms.nature.com
Carbon Dots meet Single-Atom ORR Photocatalysis rdcu.be/eTFJm 🙏Lukaš, Giorgio, María Ana and all our collabs @fau.de @solarfau.bsky.social @guldi-group.bsky.social
🇩🇪🇨🇿🇦🇷

Homomolecular Photon Upconversion in a Perylene-Decorated Iron(III) Complex Classical upconversion employs sensitizers and annihilators as two distinct molecular species and is, therefore, classified as heteromolecular. Homomolecular upconversion, the unification of both role...

A molecular dyad of an iron complex covalently bound to an annihilator exhibits three photoactive excited states — singlet, doublet, and triplet — enabling homomolecular upconversion

Florian Doettinger, Jonathan Sagaya, Giacomo Morselli in @jacs.acspublications.org

pubs.acs.org/doi/10.1021/...

Ultrafast Dissipation via Interligand Electron Transfer in {Ru(tpy)(bpy)} Chromophores With the aim of studying interligand electron transfer (ILET) with different driving forces, [Ru(tpy)(R-bpy)(CN)]+ complexes with R-bpy = 4,4′-dimethylamino-2,2′-bipyridine (dMAb), 4,4′-dimethoxy-2,2′...

Our study about dissipative ILET in {Ru(tpy)(bpy)} chromophores upon light absorption is out in Inorg. Chem. @acs.org ! it outcompetes diffusional reactivity = significant losses. Collab @solarfau.bsky.social @fau.de 🤝 Pedro Abate, Daiana Cabrosi and Luis Baraldo at UBA
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Captivating bimolecular photoredox dynamics of a ligand-to-metal charge transfer complex Transition metal complexes featuring ligand-to-metal charge transfer (LMCT) excited states have been identified as promising candidates for driving electron transfer processes. To obtain an efficient ...

Super excited to see our work monitoring dynamics of the charge separated pair in a photocycle driven by a 2LMCT exited state now out in @chemicalscience.rsc.org ! ⚡️

Thanks for the great team efforts🌟

pubs.rsc.org/en/content/a...

Spin-State and Reorganization Energy Considerations for Metal-Centered Photoredox Catalysis Transition-metal complexes featuring metal-centered excited states have recently emerged as mechanistically distinct platforms for selective photochemistry, including photoredox catalysis. Among these...

Exploring metal-centered photoredox reactivity? 🚀Don’t forget to look at the spin-state landscape and the role of reorganisation energy, they can make a difference 😉

Huge thanks to Bekah for leading the experiments and shaping the story🥳 a true collaborative effort!😃

pubs.acs.org/doi/10.1021/...

Our recent publication in collaboration with with Felix, @ludotroian.bsky.social @gioben.bsky.social was highlighted in a First Reactions article in ACS Central Science by @alextbarth.bsky.social and @fncastellano.bsky.social ! Thanks a lot!! @fau.de @solarfau.bsky.social

synthesis, absorption and emission spectrum, photoluminescence decay of a manganese(I) complex

From sub-picoseconds to 190 nanoseconds! Replacing #iron (II) by #manganese (I) gives record excited state lifetime. The paper in @natcomms.nature.com ‬reports #coherence, #photoluminescence and excited state #electrontransfer. #earth-abundant metal plus simple #carbene #ligand. rdcu.be/eBWsL

Beautiful work!!
Using fsTA, we discovered that charge separation mediates Energy Transfer in the long-lived⏳ iron complex-anthracene dyad designed and synthesized by Felix Glaser & @ludotroian.bsky.social - just published in ACS Central Science @pubs.acs.org 🥳

t.co/14xmp6kvHS

Elena Mack @guldi-group.bsky.social @solarfau.bsky.social @fau.de led our study of interfacial charge-transfer hybrids featuring TMDs and phthalocyanines. Beautiful ICT bands😍and Mulliken-Hush analysis in ACSNano @pubs.acs.org

t.co/hsvCQ4FeIl

Great news🥳! Last Friday, Ivana successfully defended her PhD thesis, becoming the 1st Doctor⚗️🥼 from our lab. Congratulations!🪇🎉
Many thanks🙏to the tribunal members Gastón Corthey, Pablo Alborés and Sandra Signorella for evaluating the 400-page thick monograph😅

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

Nature of Anti‐Dissipative High‐Energy Excited States in Quaterpyridine‐Bridged Ruthenium Complexes Upon photoexcitation, meta-connected quaterpyridine-bridged Ru complexes undergo fast inter-ligand electron transfer like typical chromophores, but unusually slow intra-ligand electron transfer withi...

Our in-depth study about how to avoid dissipation in solar-energy conversion w/ molecular chromophores is a HOT🔥paper @angewandtechemie.bsky.social @solarfau.bsky.social @fau.de In collab with fantastic @ludotroian.bsky.social & team - European WEAVE program
onlinelibrary.wiley.com/doi/full/10....

High-pressure pump–probe experiments reveal the mechanism of excited-state proton-coupled electron transfer and a shift from stepwise to concerted pathways Nature Chemistry - Chemical energy conversion and storage rely on the selective movement of protons and electrons, thus understanding these processes is important for applications. Now experiments...

This is a clever way to distinguish PCET from PT/ET pathways: using pressure.

ET/PT mechanisms lead to larger volume changes due to solvation of charged species.

@guldi-group.bsky.social @natchem.nature.com

rdcu.be/etauw

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

Excited State Dynamics of Odd [n]Cumulenes: Chain Length and Conformational Effects Over the past decades, carbon allotropes have been extensively studied and applied to various technological applications due to their unique electronic and optical properties. Contemporary research ha...

Years in the making, finally published! Congrats Bob and Yanwen, and thanks for the great collaboration ‪‪@guldi-group.bsky.social‬!

Excited State Dynamics of Odd [n]Cumulenes
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A Near-Infrared-II Luminescent and Photoactive Vanadium(II) Complex with a 760 ns Excited State Lifetime Ruthenium and iridium are key components in the most important applications of photoactive complexes, namely, light-emitting devices, photocatalysis, bioimaging, biosensing, and photodynamic therapy. ...

Long-lived #excited states with non-precious transition metals? Check Alexandra’s paper on a polypyridine #vanadium complex. #luminescence and #photocatalysis in #water published in @jacs.acspublications.org
pubs.acs.org/doi/10.1021/jacs.5c04471 #ChemSky

Abundant Transition Metal Based Photocatalysts for Red Light‐Driven Photocatalysis We discussed here the recent developments on the abundant transition metal based photocatalysts and their applications in red light-driven photocatalysis.

Our review article on red light driven photocatalysis using abundant metal based photocatalysts is now online @ChemEurJ! Please have a look if you are interested in this topic. Many thanks to the reviewers.

doi.org/10.1002/chem...

Electronic Structure with Orca: Solvent Effects in the Calculation of IR Spectra YouTube video by Prof Nicolas

New video, on how explicit solvation affects calculation of vibrations and IR spectra. Please share, like, etc! It will be appreciated!
#compchem #chemsky #science

youtu.be/yqfIN0u2X3g

Molecular Design Principles for Photoactive Transition Metal Complexes: A Guide for “Photo-Motivated” Chemists Luminescence and photochemistry involve electronically excited states that are inherently unstable and therefore spontaneously decay to electronic ground states, in most cases by nonradiative energy release that generates heat. This energy dissipation can occur on a time scale of 100 fs (∼10–13 s) and usually needs to be slowed down to at least the nanosecond (∼10–9 s) time scale for luminescence and intermolecular photochemistry to occur. This is a challenging task with many different factors to consider. An alternative emerging strategy is to target dissociative excited states that lead to metal–ligand bond homolysis on the subnanosecond time scale to access synthetically useful radicals. Based on a thorough review at the most recent advances in the field, this article aims to provide a concise guide to obtaining luminescent and photochemically useful coordination compounds with d-block elements. We hope to encourage “photo-motivated” chemists who have been reluctant to apply their synthetic and other knowledge to photophysics and photochemistry, and we intend to stimulate new approaches to the synthetic control of excited state behavior.

A simple guide to the design of metal complexes in luminescence and photoredox catalysis.

With Giacomo Morselli and Christian Reber in JACS @jacs.acspublications.org

pubs.acs.org/doi/10.1021/...

🚨 PhD Position Available! 🚨

Join our group at FAU as part of RTG 2861! 🎓🔬 We are looking for a PhD candidate to study carbon planar lattices via transient spectroscopies.

📌 Details & application: rtg2861-pcl.chm.tu-dresden.de/joboffer/

🔄 Retweets appreciated!

#chemsky #pisky #PhD #Spectroscopy

Two Birds, One Stone: Microsecond Dark Excited-State Lifetime and Large Cage Escape Yield Afforded by an Iron–Anthracene Molecular Dyad Iron photosensitizers represent a holy grail in photochemistry, but their widespread implementation is limited by their short excited-state lifetimes and poor cage escape yields. Here, the introductio...

Microsecond Dark Excited-State Lifetime and Large Cage Escape Yield Afforded by an Iron–Anthracene Molecular Dyad! Electron and energy transfer become accessible! Check out our latest work, spearheaded by the great Felix and Simon! Out in @acs.org pubs.acs.org/doi/full/10....

Iron(III) Complexes with Luminescence Lifetimes of up to 100 ns to Enhance Upconversion and Photocatalysis Iron is the most abundant transition metal element and would be the ideal replacement for noble metals in many applications that rely on luminescent and long-lived electronically excited states. We sh...

Iron(III) complexes with luminescence lifetimes as long as precious metal-based compounds

Utilization of an attached organic chromophore while maintaining a luminescent and photoactive LMCT excited state

Joel Wellauer & @bjoernpfund.bsky.social in JACS

pubs.acs.org/doi/10.1021/...

Barrierless Electron Transfer in a Photosynthetic Reaction Center Model Ultrafast IR absorption spectroscopy was utilized to interrogate excited-state electron transfer in a strongly-coupled, cyanide-bridged photoinduced mixed-valent system. Despite structural asymmetry,...

Ultrafast IR spectroscopy of photoinduced mixed-valence systems reveals a fully delocalized Class III behavior in the excited state @fau.de @guldi-group.bsky.social
onlinelibrary.wiley.com/doi/full/10....

ICP2025 The 32nd International Conference on Photochemistry will take place from July 13 (Sunday) to July 18 (Friday), 2025 in Aachen (Germany). The event is jointly organized by the RWTH Aachen University…

Registration for the 32nd International Conference on Photochemistry is now open! Secure your spot at #ICP2025 and join us in Aachen for an exciting week of cutting-edge photochemistry.

Register now at 👉 www.icp2025.de