Activating intramolecular singlet exciton fission by altering π-bridge flexibility in perylene diimide trimers for organic solar cells
We show via time resolved spectroscopy that triplet formation proceeds via intersystem crossing in a rigid-bridged perylene diimide trimer and via efficient and fast intramolecular singlet exciton fission in the analogous flexible-bridged trimer.
Driving high quantum yield NIR emission through proquinoidal linkage motifs in conjugated supermolecular arrays
Incorporation of proquinoidal BTD building blocks into conjugated porphyrin oligomers minimizes the extent of excited-state structural relaxation relative to the ground-state conformation, elucidating new classes of impressive NIR fluorophores.
Detection of magnetic field effects by confocal microscopy
Confocal microscopy is showcased as a powerful technique for the measurement of spatiotemporally-resolved magnetic field effects in both solutions and single crystals.
Photophysical implications of ring fusion, linker length, and twisting angle in a series of perylenediimide–thienoacene dimers
Ring fusion and conjugated bridge length dependent exciton dynamics and electronic coupling in a series of perylenediimide dimers with acceptor–donor–acceptor arrangement are investigated by ultrafast optical spectroscopy and TDDFT calculations.
Mutation effects on charge transport through the p58c iron–sulfur protein
Functional electron transfer between the [Fe4S4] cluster and the nucleic acid is impacted by a Y345C mutation in the p58c subunit of human primase.
Anomalous chemically induced electron spin polarization in proton-coupled electron transfer reactions: insight into radical pair dynamics
Time-resolved electron paramagnetic resonance (TREPR) spectroscopy has been used to study the proton coupled electron transfer (PCET) reaction between a Ruthenium complex (Ru(bpz)(bpy)2) and several substituted hydroquinones (HQ).
TIPS-pentacene triplet exciton generation on PbS quantum dots results from indirect sensitization
Many fundamental questions remain in the elucidation of energy migration mechanisms across the interface between semiconductor nanomaterials and molecular chromophores.
Outer-sphere effects on ligand-field excited-state dynamics: solvent dependence of high-spin to low-spin conversion in [Fe(bpy)3]2+
Time-resolved spectroscopic measurements of ground-state recovery for [Fe(bpy)3]2+ reveal that the solvent can induce an outer-sphere reorganization energy effect on excited-state dynamics involving metal-centered ligand-field electronic states.
Proton-coupled electron transfer across benzimidazole bridges in bioinspired proton wires
Experimental and theoretical methods characterize the thermodynamics of electrochemically driven proton-coupled electron transfer processes in bioinspired constructs involving multiple proton translocations over Grotthus-type proton wires.
Excited-state proton-coupled electron transfer within ion pairs
Electrostatic ion pairs provide a general method to study excited-state proton-coupled electron transfer. A PTaETb mechanism is identified for the ES-PCET oxidation of salicylate within photoexcited cationic ruthenium–salicylate ion pairs.
Electron spin polarization generated by transport of singlet and quintet multiexcitons to spin-correlated triplet pairs during singlet fissions
Singlet fission (SF) is expected to exceed the Shockley–Queisser theoretical limit of efficiency of organic solar cells.
Optical monitoring of polymerizations in droplets with high temporal dynamic range
Two complementary measurements, fluorescence polarization anisotropy and aggregation-induced emission, allow for in situ optical monitoring of polymerization reaction progress in droplets across varying temporal regimes of the reaction.
Open-circuit-voltage shift of over 0.5 V in organic photovoltaic cells induced by a minor structural difference in alkyl substituents
The cause of a large shift in open-circuit voltage induced by a minor difference in end-alkyl groups of p-type small molecules is examined via X-ray diffraction and computation, revealing a critical impact of molecular packing.
Concerted proton-electron transfer oxidation of phenols and hydrocarbons by a high-valent nickel complex
A high-valent nickel(III) compound performs fast concerted proton–electron transfer on O–H and C–H bonds. Thermodynamic analysis suggests that the oxidizing power of the compound and the formation of a strong ligand O–H bond lead to high reactivity.
The origin of the solvent dependence of fluorescence quantum yields in dipolar merocyanine dyes
An increasing activation energy barrier to a conical intersection was identified as the reason for higher fluorescence lifetimes and quantum yields for merocyanines in polar solvents.
Facile synthesis of fluorescent heterocirculene analogues with tunable solubilities and optical properties
Highly twisted quasi-azacirculene and planar triazaoxacirculene have been prepared, which exhibited intriguing optical properties.
Subphthalocyanine–tetracyanobuta-1,3-diene–aniline conjugates: stereoisomerism and photophysical properties
We report the stereoisomerism and physicochemical properties of two novel electron donor–acceptor conjugates based on subphthalocyanines decorated at their peripheral, or peripheral/axial positions with multiple tetracyanobutadiene–aniline moieties.
About this collection
Michael Wasielewski is a pivotal figure in artificial photosynthesis, molecular self-assembly, photochemistry, organic magnetism, and spintronics. These papers from colleagues and collaborators, all of them friends, celebrate Mike’s science and vision.