Machine learning Methods and Software
A Simple Solution for Machine Learning of Vector Quantities
Effortlessly achieve rotationally invariant machine learning of vectors with the rotate-predict-rotate (RPR) method.
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Methods and Software
QDCT: A New Strategy for Nonadiabatic Molecular Dynamics
QDCT seamlessly enhances surface hopping accuracy without adding computational cost.
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Photochemistry and photophysics
Internal Conversion Pathways of Resveratrol
Discovering the photophysics of resveratrol opens up its use in pharmaceutical innovations.
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Quantum mechanics
Gravity Induced Wave-Function Collapse
Exploring the Diósi-Penrose model and its implications for quantum mechanics
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Science popularization
The Many Answers to the Quantum Measurement Problem
What do we know (and don’t know) about quantum collapse?
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Methods and Software
Software ecosystem for surface hopping in Python
Quantum mechanical and machine learning dynamics with MLatom
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Photochemistry and photophysics
The reason ISC is faster in seleno- than in thioguanine
Hint: it isn’t only about SOC!
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Photochemistry and photophysics
Cyclobutanone Prediction Challenge
How well can nonadiabatic dynamics forecast an experiment?
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Methods and Software
Recommendations for velocity rescaling after hopping
Benchmark compares different ways to rescale velocities in surface hopping.
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Spectroscopy
Auger-Meitner and X-ray Absorption Spectra of Ethylene Cation
X-Ray simulations reveal twisting in ethylene cation internal conversion.
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Photochemistry and photophysics Spectroscopy
Photodynamics of sinapate esters: a matter of shape
Excited-state lifetime is deeply affected by the conical intersection topography.
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Photochemistry and photophysics Spectroscopy
Temperature-dependence in adenosine internal conversion
Intramolecular energy transfer at low temperatures delays adenosine’s internal conversion.
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Science popularization
We are not empty
The concept of the atomic void is one of the most repeated mistakes in popular science. Molecules are packed with stuff.
Photochemistry and photophysics Spectroscopy
Phosphorescence lifetime of aromatic carbonyls
Phosphorescence of aromatic carbonyls takes much longer from ππ* than from nπ*. We explain why.
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Science popularization
Authorship in time of ChatGPT
ChatGPT and other generative AI language models will profoundly impact how we write.
Photochemistry and photophysics
Classification of Doubly Excited Molecular Electronic States
A physically motivated definition of doubly excited character based on density matrices is proposed.
Photochemistry and photophysics Review
Modeling charge and energy transfer in active environments
Surface hopping is the leading approach to help understand excited molecules in active environments.
Machine learning
WS22 Molecular Dataset
A quantum sampled molecular
dataset ups the challenge of training ML models.
Photochemistry and photophysics
Ultrafast photoisomerization dynamics in sinapate esters
Unexpected complex isomerization dynamics of ethyl sinapate.
Photochemistry and photophysics
Non-Kasha fluorescence of pyrene
Simulation confirms pyrene spectral shoulder is from non-Kasha emission.
Review
Excited-state dynamics with machine learning
Book chapter discusses practical aspects of how to use ML for exited-state dynamics.
Organic photodevices
Using π electrons to control doubly-excited states
Energetic stability of doubly-excited states depends on the number of π electrons.
Quantum chemistry
Ultrafast internal conversion without energy crossing
Theory shows conditions for having sub-ps lifetime without conical intersections.
Methods and Software
Surface hopping with polarizable force fields
Newton-X, G16, and Tinker together for TDDFT/LR-AMOEBA dynamics.
Photochemistry and photophysics
H-bond’s role in adenosine’s photophysics
H-bond promotes ring-puckering in adenosine.
Methods and Software
Correcting ZPE leakage in dynamics
A hessian-free method to avoid ZPE leakage in quasi-classical dynamics is available.
Quantum chemistry
Is Boltzmann’s S = k log W right?
Boltzmann and Gibbs proposed different formulations for statistical physics. Which one is correct?
Photochemistry and photophysics
Ultrafast internal conversion at large energy gaps
Dynamics simulations show 100-fs internal conversion at 0.5-eV gaps.
Photochemistry and photophysics
Heating and cooling a chromophore after photoexcitation
How long does it take to transfer energy from a hot molecule to a solvent? We have the answer.
Methods and Software
Simulations of molecular photodynamics in long timescales
Step-by-step, everything we need for nanosecond simulations.
Spectroscopy
Electron delocalisation probed by resonant Auger
Resonant Auger spectroscopy probes conjugation effects in core-excited aromatic molecules.
Photochemistry and photophysics
Novel Molecular Light-to-Heat Converters
Barbituric derivatives are a green option for photothermal applications.
Methods and Software
Choosing the right molecular machine learning potential
This article offers a lifeline for those lost in the sea of molecular machine learning potentials.
Photochemistry and photophysics
Photophysics of UVA Filters Based on Meldrum Derivatives
Meldruns photophysics follows a two-step logistic decay through a charge-transfer state.
Methods and Software
Surface Hopping with Baeck-An Couplings
New method enables nonadiabatic dynamics based on energy-gaps’ time-derivatives.
Methods and Software
Does Velocity Adjustment Direction Affect Surface Hopping Dynamics?
For a small trajectory number, errors are not significant.
Organic photodevices
How Do Excitons’ Size and Density Depend on Heterojunction’s Architecture?
Simulations show how to control charge separation from hot or cold excitons.
Organic photodevices
Excitons and Charge Transfer in Tetracene Dimers
Stacked-excimer double excitation is the door for singlet fission.
Photochemistry and photophysics
A New Generation UV‑A Filters
Meldrum phenolics proposed as a new class of UV-A filters.
Quantum chemistry Review
TDDFT: from the fundamentals to nonadiabatic dynamics
Book chapter delivers a “best-practice” guide on TDDFT.
Methods and Software
Nonadiabatic Dynamics with Complex Potential Energies
New dynamics method for dissipative processes.
Methods and Software Quantum chemistry
Talk: Simulating Thermal Light
In this talk, I explain the basis of the Chenu-Brumer approach for thermal light, and how it can be used in mixed quantum-classical dynamics.
Methods and Software
Machine Learning for Nuclear Ensembles
Machine learning enables high-precision spectrum simulations.
Productivity Scientific policy
What’s the Best Open Access Option?
All you need to know about open access.
Methods and Software
Dynamics Induced by Sunlight
New method allows excited-state simulations induced by thermal light.
Quantum chemistry
Why Are Vertical Excitations and Band Maxima Shifted?
Shift between Vexc and Bmax is caused by frequency changes.
Organic photodevices
Nonadiabatic Dynamics of Anthracene-Tetracyanoethylene Complex
Protic environment creates an ion-pair CT ground state.
Methods and Software
Multireference calculations with COLUMBUS
COLUMBUS is one of the most flexible programs for MRCI and MCSCF.
Quantum chemistry
#StayAtHome II. Singlet Oxygen
I have recorded a talk on “Singlet Oxygen Photosensitization in Weakly Coupled Floppy Complexes” and made it available on YouTube. This is my contribution to the #StayAtHome. Part 1/2 Part 2/2
Quantum chemistry
#StayAtHome I. Dynamics
I have recorded a talk on “Advances and Perspectives on Mixed Quantum-Classical Dynamics” and made it available on YouTube. This is my contribution to the #StayAtHome.
Science popularization
As Small As an Atom
Things have no well-defined position; light doesn’t illuminate. Seen from the Angstrom scale—the size of an atom, the universe is a pretty weird place. (more…)
Science popularization
Just wait a femtosec, please
When you stand up, your head gets older faster than your feet by one femtosecond every ten seconds. This and eight other facts about the femtosecond you never thought of. (more…)
Methods and Software Quantum chemistry
On-the-fly Dynamics of Transient Anions
A new method allows simulating transient anions dynamics with mixed quantum-classical techniques.
Quantum chemistry
2019 Conference on Light and Molecules
The 2019 Conference on Light and Molecules is bringing together researchers from France, Sweden, USA, Canada, Brazil, China, Thailand, and South Korea to discuss their latest results in experimental and theoretical physical chemistry. To know more, check: http://icr-amu.cnrs.fr/tct/lightmol2019/ MB
Photochemistry and photophysics
Boosting Charge Transfer in an Organic Photocatalyst
Attaching an electron donor group to the chromophore can speed up electron transfer.
Scientific policy
Three Reasons to Invest in Science
Investing in science pays off, even when the results are null.
Organic photodevices
Biazobenzene ring shows strong stereoselectivity upon photoexcitation
Cyclobiazobenzene twists clockwise in three out of four UV excitations.
Research project
BoostCrop: Light for Food Security
A European team has been commissioned to develop a substance to protect crops against cold stress.
Photochemistry and photophysics
Photodissociation of cyclohexadiene with CASPT2 dynamics
Paper sets a new gold-standard for surface hopping.
Productivity
From lab into papers: tips for efficient academic work
This is how you get your work published.
Research project
SubNano ERC AdG 2019
I’ve been awarded an ERC AdG to develop methods for ns nonadiabatic dynamics.
Organic photodevices
How to activate phosphorescence in a fluorescent molecule
Chemical induction of a CT state can restrain fluorescence, promoting ISC.
Atmospheric photochemistry
Chlorine elimination in HCFC-133a
UV-excited HCFC-133a eliminates Cl– through an ion-pair complex.
Photosensitization and singlet oxygen Quantum chemistry
Spin-Exchange Internal Conversion (SEIC)
Simple proxies can predict diabatic and nonadiabatic couplings.
Organic photodevices
Dynamics of Benzene Excimer Formation
Bezene excimers are formed within 1 ps and die after 0.3 ps.
Organic photodevices
High-Resolution NEXAFS for Condensed Polyacenes
Chemically different carbons cause dichroism in X-ray excitation of polyacenes.
Photochemistry and photophysics
Nonadiabatic Dynamics of Urocanic Acid
Dynamics shows that quantum-yield dependence on excitation energy doesn’t occur in the gas phase.
Methods and Software
Nonadiabatic Dynamics with Machine Learning
Machine learning can reduce dynamics cost by a factor of ten.
Photochemistry and photophysics
Intersystem crossing in 4-thiouracil
Multiscale photo-relaxation of thiouracil is resolved through theory and experiments.
Atmospheric photochemistry
Photochemistry of CFC-13
Anomalous charge quenching of CF3Cl is caused by internal conversion.
Photochemistry and photophysics
Dynamics of UV-Excited Thymine-Water Cluster
UV radiation triggers water evaporation within 30 fs.
Review
Multireference Approaches for Excited States of Molecules
Paper reviews multireference methods and applications to molecular excited states.
Photosensitization and singlet oxygen
Influence of Sugar on Triplet Decay of Thionucleosides
Functionalization of the sugar group can be used to control the triplet-decay rate of thionucleosides.
Review
Advances in Nonadiabatic Mixed Quantum-Classical Dynamics
Paper reviews the last ten years of developments in nonadiabatic dynamics.
Methods and Software
Nuclear Ensemble with Importance Sampling
Mapping between probability distributions can save a lot of time in dynamics and spectrum simulations.
Quantum chemistry
How Many Trajectories Should I Run?
Want to do dynamics? This is how many trajectories you will need. (more…)
Methods and Software
Surface Hopping with TD-DFTB
Interface between Newton-X, DFTB+, and TheoDORE enables nonadiabatic dynamics at nanoscale.
Photosensitization and singlet oxygen
Singlet Oxygen: Rates Strongly Depend on Geometry
Simulations show how to maximize reaction rates for singlet oxygen generation.
Methods and Software
A Kinetic Model for Singlet Oxygen Photogeneration
Reaction rates for energy transfer calculated from first principles.
Organic photodevices
Hot and Cold Charge Transfer in Organic Donor/Acceptor Interfaces
Charge separation follows different photophysics in different donor/acceptor arrangements.
Photochemistry and photophysics
Three-state Model for the Photo-Fries Rearrangement
Photo-Fries rearrangement plays a central role in organic synthesis. But how does it really work?
Organic photodevices
Photophysics of Sulfur-Bridged Naphthalene Dimers
Sulfur bridge’s oxidation state dramatically changes the photoluminescence of bichromophores. That’s why.
Photosensitization and singlet oxygen
On the Decay of the Triplet State of Thionucleobases
Double-well shaped triplet state in thionucleobases can be used to tune singlet oxygen yields.
Quantum chemistry
What’s the Biggest System We Can Do Dynamics?
Want to do dynamics? This is how much it’ll cost.
Photochemistry and photophysics
Tailoring Schiff Bases Photoswitching
Dynamics reveals how to design chemical substitutions to control proton transfer efficiency.
Methods and Software
Spin-Orbit Couplings Based on Density Functional Theory
PySOC, a new program for fast and flexible computation of spin-orbit couplings.
Photochemistry and photophysics
Revisiting the Excited State Dynamics of Thymine
So far, the long lifetime of UV-excited thymine has been explained in terms of trapping in the second excited state. Simulations with electron correlation shows this hypothesis doesn’t hold.
Atmospheric photochemistry Quantum chemistry
The Halons-9 Molecular Set
A new molecular set composed of small haloorganic compounds shows that popular computational methods may have errors of about 0.8 eV.
Methods and Software
Photoelectron Spectrum Simulations
Methods based on nuclear ensembles allow to simulate steady and time-resolved photoelectron spectra with absolute intensities.
Photochemistry and photophysics
Guanidinium: A New Analytical Tool to Detect Anions
Chromophore-guanidine compounds can be used as selective anion sensors.
Photosensitization and singlet oxygen
Explaining the Photophysics of Thiothymines
Why does replacing different oxygens of thymine with sulfur cause distinct absorption and intersystem crossing?
Organic photodevices
Organic Photovoltaics: Make Light, Not Heat
A new approach based on dynamics simulations is proposed to boost the efficiency of organic photovoltaics.
Atmospheric photochemistry Quantum chemistry
Chlorine Hydrogen Bonds? Yes, They do Exist
CH∙∙∙Cl hydrogen bond in chloromethane may be formed by UV irradiation.
Atmospheric photochemistry
Nonadiabatic Dynamics of HCFC-132b
HCFC-132b is an important industrial compound with strong environmental impact. Nonadiabatic dynamics explains how UV induces its photo-decomposition in the sub-picosecond scale.