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Concept

Règle de l'octet

Publications associées (20)

Development of Hetero-Vinylbenziodoxolone Reagents for Applications in Synthetic Methodology and Biomolecule Functionalization

Nina Declas

Among the numerous existing chemical motifs, alkenes, alkynes, enol ethers and enamides, with an unsaturated carbon-carbon bond, are versatile functional groups that are found in many natural products and bioactive compounds. They are widely used as valuab ...

EPFL2023

koopmans: An Open-Source Package for Accurately and Efficiently Predicting Spectral Properties with Koopmans Functionals

Nicola Marzari, Nicola Colonna, Edward Baxter Linscott, Ngoc Linh Nguyen, Giovanni Borghi, Riccardo De Gennaro

Over the past decade we have developed Koopmans functionals, a computationally efficient approach for predicting spectral properties with an orbital-density-dependent functional framework. These functionals impose a generalized piecewise linearity conditio ...

Amer Chemical Soc2023

Search for long-lasting electronic coherence using on-the-fly ab initio semiclassical dynamics

Jiri Vanicek, Nikolay Golubev, Alan Scheidegger

Using a combination of high-level ab initio electronic structure methods with efficient on-the-fly semiclassical evaluation of nuclear dynamics, we performed a massive scan of small polyatomic molecules searching for a long-lasting oscillatory dynamics of ...

AIP Publishing2022

Using collective knowledge to assign oxidation states of metal cations in metal-organic frameworks

Berend Smit, Seyedmohamad Moosavi, Kevin Maik Jablonka, Daniele Ongari

Knowledge of the oxidation state of metal centres in compounds and materials helps in the understanding of their chemical bonding and properties. Chemists have developed theories to predict oxidation states based on electron-counting rules, but these can f ...

NATURE RESEARCH2021

Core-Valence Attosecond Transient Absorption Spectroscopy of Polyatomic Molecules

Jiri Vanicek, Nikolay Golubev

Tracing ultrafast processes induced by interaction of light with matter is often very challenging. In molecular systems, the initially created electronic coherence becomes damped by the slow nuclear rearrangement on a femtosecond timescale which makes real ...

2021

Band alignment at beta-Ga2O3/III-N (III = Al, Ga) interfaces through hybrid functional calculations

Alfredo Pasquarello, Sai Lyu

The band alignment and the chemical bonding at the beta -Ga2O3/AlN and beta -Ga2O3/GaN interfaces are studied through hybrid functional calculations. We construct realistic slab models with III-O (III = Al, Ga) bonds dominating the chemical bonding at both ...

2020

Local structural investigation of hafnia-zirconia polymorphs in powders and thin films by X-ray absorption spectroscopy

Reinis Ignatans

Despite increasing attention for the recently found ferro- and antiferroelectric properties, the polymorphism in hafnia- and zirconia-based thin films is still not sufficiently understood. In the present work, we show that it is important to have a good qu ...

PERGAMON-ELSEVIER SCIENCE LTD2019

Orientational ordering of water in extended hydration shells of cations is ion-specific and is correlated directly with viscosity and hydration free energy

Sylvie Roke, Yixing Chen, Halil Ibrahim Okur, Chung-Wen Liang

Specific ion effects in aqueous solutions are investigated at the molecular, nanoscopic and macroscopic levels. Femtosecond elastic second harmonic scattering (fs-ESHS) is used here to assess the chemical effects of ions on molecular and nanoscopic length ...

2017

Molecular mechanism of NDMA formation from N,N-dimethylsulfamide during ozonation: Quantum chemical insights into a bromide-catalyzed pathway

Urs von Gunten, Jeremy Samuel Arey, Daniela Trogolo, Michèle Bernadette Heeb, Brijesh Kumar Mishra

During ozonation of drinking water, the fungicide metabolite NN-dimethyIsulfamide (DMS) can be transformed into a highly toxic product, N-nitrosodimethylamine (NDMA). We used quantum chemical computations and stopped-flow experiments to evaluate a chemical ...

Amer Chemical Soc2015

Exploration of zeroth-order Wavefunctions and Energies for Intramolecular Symmetry-Adapted Perturbation Theory

Anne-Clémence Corminboeuf, Jérôme Florian Gonthier

Non-covalent interactions occur between and within all molecules and have a profound impact on structural and electronic phenomena in chemistry, biology, and material science. Understanding the nature of inter-and intramolecular interactions is essential n ...

Amer Inst Physics2014

Modern computational approaches for quantifying inter- and intramolecular interactions

Jérôme Florian Gonthier

This thesis introduces modern computational approaches for quantifying and analyzing both intra- and intermolecular interactions. An original formalism to quantify intramolecular interactions ab initio is first introduced. Inspired from intermolecular Symm ...

EPFL2013

Accurate determination of charge transition levels of the As-As dimer defect at GaAs/oxide interfaces through hybrid functionals

Alfredo Pasquarello, Giacomo Francesco Leonardo Miceli

The energy levels of the As-As dimer defect at GaAs/oxide interfaces are accurately determined within a hybrid functional scheme and aligned with respect to the GaAs band gap. An As-As dimer is constructed at a model interface between GaAs and kappa-Al2O3, ...

2013

Multicomponent Assembly of Boronic Acid-Based Macrocycles, Cages, and Polymers

Burçak Içli

This work describes the synthesis and characterization of boronic acid-based supramolecular structures. Different reversible interactions such as boronate ester formation, imine condensation and dative B–N bond formation are used to assemble macrocycles, c ...

EPFL2012

Structure-Correlation Principles Connecting Ground State Properties and Reaction Barrier Heights for the Cope Rearrangement of Semibullvalenes

Anne-Clémence Corminboeuf, Matthew Wodrich, Daniel Filipe Dos Santos Alves Jana

A direct relationship exists between the properties of substituted semibullvalenes and their Cope rearrangement activation barrier. This unique correlation not only enables the determination of kinetic data from ground state information, but also provides ...

American Chemical Society2012

Spectroscopy on Rydberg states of sodium atoms on the surface of helium nanodroplets

Marcel Drabbels, Evgeniy Loginov

One- and two-photon excitation spectra of sodium atoms on the surface of helium droplets are reported. The spectra are recorded by monitoring the photoionization yield of desorbed atoms as function of excitation frequency. The excitation spectra involving ...

American Chemical Society2011

IR spectroscopy of isolated metal-organic complexes of biocatalytic interest: Evidence for coordination number four for Zn2+(imidazole)(4)

Ulrich Lorenz

The characterization of the interactions of Zn2+ ions with imidazole ligands is vital for understanding the function of a plethora of zinc enzymes at the molecular level. The infrared multiple photon dissociation (IRMPD) spectrum of mass selected Zn2+(imid ...

2011

Multifrequency EPR studies of zero field splitting of Gd(III) based MRI contrast agents in solids and liquids

Magnetic Resonance Imaging (MRI) offers an amazing number of ways to probe the human body. It is a wonderful symbiosis of engineering, science and medicine. The power of MRI is its ability to probe a variety of physical mechanisms that can then not only re ...

EPFL2006

Scanning Reactive Pathways with Orbital Biased Molecular Dynamics

Ursula Röthlisberger, Leonardo Guidoni

To accelerate reactive events in mol. dynamics simulations we introduce a general bias potential scheme which depends only on the electronic degrees of freedom of the reactive system. This electronic reaction coordinate, which is expressed in terms of a pe ...

2005

Quantum mechanical/molecular mechanical (QM/MM) Car-Parrinello simulations in excited states

Ursula Röthlisberger, Ivano Tavernelli, Leonardo Guidoni, Enrico Marko Tapavicza

The combination of time-dependent d. functional theory (TDDFT) for the description of excited states with a hybrid quantum mechanics/mol. mechanics (QM/MM) approach enables the study of photochem. processes in complex environments. Here, we present a short ...

2005

Photoelectric conversion device

Michael Graetzel, Shaik Mohammed Zakeeruddin, Peng Wang

Photoelectric conversion device (1) comprising semiconductor electrode (15) having semiconductor layer (7) carrying a sensitizing dye, counter electrode (9) arranged opposite to the semiconductor electrode (15) and electrolyte layer (13) arranged between t ...

2003