A5030929537- Organic Electronics and Photovoltaics
- Photochromic and Fluorescence Chemistry
- Photoreceptor and optogenetics research
- Photochemistry and Electron Transfer Studies
- Synthesis and Properties of Aromatic Compounds
- Force Microscopy Techniques and Applications
- Porphyrin and Phthalocyanine Chemistry
- Protein Structure and Dynamics
- Organic Chemistry Cycloaddition Reactions
- Enzyme Structure and Function
- Thin-Film Transistor Technologies
- Crystallization and Solubility Studies
- Chalcogenide Semiconductor Thin Films
- Conducting polymers and applications
- X-ray Diffraction in Crystallography
- Analytical Chemistry and Chromatography
- Machine Learning in Materials Science
- Electron and X-Ray Spectroscopy Techniques
- Quantum Dots Synthesis And Properties
- Spectroscopy and Quantum Chemical Studies
- Fullerene Chemistry and Applications
- CCD and CMOS Imaging Sensors
- Radiation Detection and Scintillator Technologies
- Perovskite Materials and Applications
- Material Dynamics and Properties
Technical University of Denmark
2019-2024
University of Copenhagen
2016-2023
Lund University
2021
Argonne National Laboratory
2021
High Energy Accelerator Research Organization
2021
Japan Synchrotron Radiation Research Institute
2021
Universität Hamburg
2020
Max Planck Institute for the Structure and Dynamics of Matter
2020
Hamburg Centre for Ultrafast Imaging
2020
Center for Free-Electron Laser Science
2020
Abstract The recent re‐parametrization of the Martini coarse‐grained force field, 3, improved accuracy model in predicting molecular packing and interactions dynamics simulations. Here, we describe how small molecules can be accurately parametrized within 3 framework present a database validated molecule models. We pay particular attention to description aliphatic aromatic ring‐like structures, which are ubiquitous such as solvents drugs or building blocks constituting macromolecules...
Abstract Organic solar cells have recently experienced a substantial leap in power conversion efficiency, part driven by formulations with new non-fullerene acceptors. This has brought the technology past psychologically important mark of 15% efficiency for unscaled laboratory devices, and results are stimulating another burst research activity. Whether this will propel into viable commercial contender yet to be determined, but realize potential organic utility scale application, fabrication...
Abstract Photochemical conversion of molecules into high‐energy isomers that, after a stimulus, return to the original isomer presents closed‐cycle light‐harvesting, energy storage, and release. One challenge is achieve sufficiently high storage capacity. Here, we present efforts tune dihydroazulene/vinylheptafulvene (DHA/VHF) couple through loss/gain aromaticity. Two derivatives were prepared, one with aromatic stabilization DHA second VHF. The consequences for switching properties...
The nature of interchain π-system contacts, and their relationship to hole transport, are elucidated for the high-mobility, noncrystalline conjugated polymer C16-IDTBT by application scanning tunneling microscopy, molecular dynamics, quantum chemical calculations. microstructure is shown favor an unusual packing motif in which paired chains cross-over one another at near-perpendicular angles. By linking mesoscale microstructural features, revealed coarse-grained dynamics previous studies,...
Nonfullerene acceptors have caused a step change in organic optoelectronics research but little is known about the mechanism and factors limiting charge transport these molecular materials. Here joint computational-experimental investigation presented to understand impact of various sources disorder on electron nonfullerene acceptor O-IDTBR. We find that single crystals this material, occurs transient quantum delocalization regime with excess delocalized over three molecules average,...
Abstract A method is presented to manipulate the final morphology of roll‐to‐roll slot‐die coated poly(3‐hexylthiophene) (P3HT) by optically exciting p‐type polymer in solution while coating. These results provide a comprehensive picture entire knowledge chain, from demonstrating how apply authors’ fundamental understanding changes and physical properties induced P3HT By combining density functional theory molecular dynamics simulations with variety X‐ray experiments, absorption...
Molecular solar thermal (MOST) systems that undergo photoisomerizations to long-lived, high-energy forms present one approach of addressing the challenge energy storage. For this mature, photochromic molecules which can absorb at right wavelengths and store a sufficient amount in controlled time period have be developed. Here we show combined experimental theoretical study incorporation pyridyl substituent onto dihydroazulene/vinylheptafulvene photo-/thermoswitch results whose optical...
We present a procedure for simulating solution deposition of organic thin-films on explicitly modeled substrates via solvent evaporation simulations in molecular dynamics framework. Additionally, we have developed force fields the family IDTBR nonfullerene acceptors, which been widely employed literature as $n$-type materials several types semiconductor devices, and analyzed their structure-property relationships using combination grazing incidence x-ray scattering measurements, atomistic...
Photon upconversion facilitated by triplet-triplet annihilation in molecular systems is a promising path toward utilization of sub bandgap photons photovoltaic devices. Prior to the challenging synthesis new molecules, quantum chemical computations can aid design process and provide suggestions for optimal systems. Here, we benchmark time-dependent density functional methods their ability describe relevant photophysical quantities range different types sensitizer/annihilator pairs guidelines...
Former work has improved the energy storage capacity of dihydroazulene/vinylheptafulvene photo/thermoswitch by substitution with NH2 and NO2 in vacuum. This extends former investigating solvent effects systematically using cyclohexane, toluene, dichloromethane, ethanol, acetonitrile comparing them inclusion vacuum calculations. The investigation includes more than 8000 calculations density functional theory for comparison capacities, activation energies thermal conversion vinylheptafulvene...
Development of photochromic molecules for solar energy storage has two major challenges: (i) to store a sufficient amount in the metastable isomer and (ii) control energy-releasing step, i.e., setting it on hold until is needed. Combining dihydroazulene/vinylheptafulvene (DHA/VHF) photo-/thermoswitch with dithienylethene/dihydrothienobenzothiophene (DTE/DHB) photoswitch could potentially meet these challenges. The combined multimode switch studied by density functional theory order predict...
Abstract The gain and loss of aromaticity plays a key role in organic chemistry the prediction rate‐determining steps. Herein, we explore concept photoisomerization reactions. Benzannulated derivatives dihydroazulene‐vinylheptafulvene (DHA‐VHF) photoswitch were investigated using transient absorption spectroscopy time‐dependent density functional theory to elucidate effect built‐in on switching properties. We found that benzannulation hampered ability by enhancing an already existing barrier...
To date, alternating co-polymers based on electron-rich and electron-poor units are the most attractive materials to control functionality of organic semiconductor layers in which ultrafast excited-state processes play a key role. We present computational study photoinduced dynamics 4-(2-thienyl)-2,1,3-benzothiadiazole (BT-1T) molecule, is common building block backbone π-conjugated polymers used for electronics. In contrast homo-polymer materials, such as oligothiophene, BT-1T has two...
The recent re-parametrization of the Martini coarse-grained force field, 3, improved accuracy model in predicting molecular packing and interactions dynamics simulations. Here, we describe how small molecules can be accurately parametrized within 3 framework present a database validated molecule models (available at https://github.com/ricalessandri/ Martini3-small-molecules http://cgmartini.nl). We pay particular attention to description aliphatic aromatic ring-like structures, which are...
The recent re-parametrization of the Martini coarse-grained force field, 3, improved accuracy model in predicting molecular packing and interactions dynamics simulations. Here, we describe how small molecules can be accurately parametrized within 3 framework present a database validated molecule models (available at https://github.com/ricalessandri/ Martini3-small-molecules http://cgmartini.nl). We pay particular attention to description aliphatic aromatic ring-like structures, which are...
Roll-To-Roll Slot-Die Coating In article number 2212835, Jens Wenzel Andreasen and co-workers study the optical excitation during roll-to-roll slot-die coating of a semiconducting polymer that enables morphological manipulation thin-films for organic photovoltaics flexible electronics. Combined theoretical experimental techniques elucidate changes upon while thin-film solidifies. The induced in nanostructure increase out-of-plane electron mobility, which may be applied to modify performance...
Abstract The front cover artwork is provided by the Hansen and Mikkelsen groups from University of Copenhagen. image shows how excited state aromaticity affects photochemistry dihydroazulene (DHA). Inducing enhances an barrier, so DHA can no longer reach photoproduct. Read full text Article at 10.1002/cptc.201900088 .
Ultrafast, light-induced dynamics in copper–zinc–tin–sulfide (CZTS) photovoltaic nanoparticles are investigated through a combination of optical and x-ray transient absorption spectroscopy. Laser-pump, x-ray-probe spectroscopy on colloidal CZTS nanoparticle ink yields element-specificity, which reveals rapid photo-induced shift electron density away from Cu-sites, affecting the molecular orbital occupation structure CZTS. We observe formation stable charge-separated thermally excited...
We have investigated the switching mechanisms of photochromic systems that are relevant for harvesting, storing, and releasing solar energy. consider storage energy in form energetic chemical bonds via light-induced isomerization reactions. The approach concerns photoswitches upon irradiation isomerize to high-energy metastable isomers through corresponding backreaction will release stored Thereby, we considered molecular closed-cycle do not involve CO2 . present potential surfaces ground...