WorldCat Identities

Michel, Carine (1980-....).

Overview
Works: 16 works in 18 publications in 2 languages and 20 library holdings
Roles: Opponent, Thesis advisor, Author, Other
Publication Timeline
.
Most widely held works by Carine Michel
Études théoriques de la réactivité chimique by Carine Michel( Book )

3 editions published in 2007 in French and held by 3 WorldCat member libraries worldwide

Stakes and difficulties of theoretical studies of chemical reactivity are highlighted through various chemical systems: phosphatase biomimetic complexe, tandem acetalisation/cyclisation reaction, Pauson-Khand reaction. This last study even lead us to propose a new electropsray source calibration.To go beyong the traditionnal methods limits, we used the metadynamics method, which can sample the phase space of chemical systems and overcome rare events problem. Associated with ab initia Born-Oppenheimer dynamics, we have demonstrated that metadynamics can be efficient to study organometallics reactions. Furthermore, we have initiated a novel strategy to evaluate directly entropy thanks to metadynamics. The first results are promising, as weIl as in organometallics reactivity than in water dimer dissociation
Heterogeneous Transformation of Glycerol to Lactic Acid by Florian Auneau( )

1 edition published in 2012 in English and held by 2 WorldCat member libraries worldwide

Chemins de protonation et réactivité des métalloenzymes : application à la superoxide réductase by David Rolf( )

1 edition published in 2017 in French and held by 2 WorldCat member libraries worldwide

Obtaining targeted molecules under gentle, selective and sustainable conditions is still a major challenge. Artificial metalloenzymes are animportant line of enquiry, because by playing, for example, with the second sphere of coordination, it is possible to strongly modify thereactivity of these bio-inspired systems. The development of this chemistry presupposes a thorough knowledge of the different stages of themechanism of the reaction under study. For this reason, theoretical chemistry is essential to rationalize chemical reactivity, but it still suffersfrom many shortcomings for the systems we propose to study.In this work, we study the superoxide reductase, a detoxifying enzyme of the superoxide radical. While many experiments are available detailingsome intermediates, the precise mechanism is not well documented. The aim was to implement a complete methodology ranging from thedevelopment of specific MM parameters to the study of reactivity by QM/MM metadynamics.The development of MM parameters for the iron active site allowed its study by MM dynamics giving informations on the conformation ofthe peptide backbone as well as on the interaction with solvent molecules. Due to the nature of the iron, a QM description of the active sitewas required using hybrid DFT. QM/MM metadynamics have allowed us to explore reaction pathways and to characterize the compoundsformed to obtain the needed activation energies. This methodology made it possible to understand the native reactivity of the wild form ofthe SOR, but also to explore the new reactivity of the mutations of the SOR and thus to define the crucial role of the second coordination sphere
Linear energy relations for biomass transformation under heterogeneous catalysis : a fast prediction of polyalcohol dehydrogenation on transition metals by Jérémie Zaffran( )

1 edition published in 2014 in English and held by 1 WorldCat member library worldwide

La valorisation de la biomasse est une alternative intéressante aux ressources fossiles, et s'effectue fréquemment en catalyse hétérogène. L'élaboration de nouveaux catalyseurs est une tâche ardue qui peut être considérablement accélérée in silico. Cependant les molécules de la biomasse sont souvent complexes et hautement oxygénées, rendant ainsi les calculs plus difficiles et couteux en temps. Parmi ces composés, les polyols sont particulièrement importants. Nous avons développé des relations du type Brønsted-Evans-Polanyi (BEP) à partir d'une étude DFT menée sur une famille de monoalcools concernant les dissociations des liaisons C-H et O-H sur des catalyseurs métalliques (Co, Ni, Ru, Rh, Pd, Ir, Pt). Ces relations ont pour but de prédire l'énergie d'activation d'une étape élémentaire à partir de son énergie de réaction. La précision obtenue par ces modèles linéaires est supérieure à 0.10 eV pour l'échantillon considéré. Ces relations ont ensuite étaient appliquées aux étapes élémentaires de la déshydrogénation du glycérol, choisi comme polyol prototype. On observe une erreur moyenne inférieure à 0.10 eV et une erreur systématique de l'ordre de ± 0.10 eV sur Rh. Etant donné que la principale différence entre les monoalcools et le glycérol, vient des liaisons H intramoléculaires présentes dans celui-ci, nous avons mis en place des relations linéaires pour prédire la déshydrogénation des monoalcools assistée par l'eau. Ces nouvelles relations nous ont permis d'améliorer la prédiction sur le glycérol et même d'éliminer la déviation systématique dans le cas de la rupture de la liaison OH. Même si dans cette étude nous nous sommes focalisés sur la déshydrogénation du glycérol, des méthodes similaires pourraient être appliquées à d'autres polyols avec d'autres réactions chimiques, accélérant ainsi considérablement la recherche in silico de catalyseurs solides. Ce travail pave la route pour le développement de nouvelles techniques numériques pour aborder la question de la conversion de la biomasse
Modélisation d'effets de solvant pour des réseaux réactionnels étendus de la biomasse en catalyse hétérogène by Benjamin Schweitzer( )

1 edition published in 2018 in French and held by 1 WorldCat member library worldwide

This thesis focuses on multi scale simulations heterogeneous catalysis reactions of polyols on platinum (111) in aqueous phase. This work is about lignocellulosic biomass valorisation. The reaction networks raising from these materials are extremely large and complex. Also, the properties of the molecules forming this biomass make aqueous conditions mandatory. Ab initio methods as we know them forbids us to treat entire networks at the finest calculation level, the computational cost would be way beyond feasibility. Changing the simulation scale can tackle this problem. Thus, we developed a group additivity model assessing for thermochemical properties of polyols at a platinum (111) surface under aqueous conditions, with a topology as the only input. This model was built upon a density functional theory set. Kinetics of reactions was also covered, and the difference in terms of impact was investigated between implicit and explicit micro solvation models, in order to predict reaction barriers. The two models might be used together in order to feed a micro kinetic simulation, allowing a drastic decrease of reaction networks complexity. Finally, the influence on reactivity and selectivity, of hydroxyl groups on butanediol isomers was investigated
Biomass reactions on heterogeneous catalysts : computational studies on surface determination and reactivity by Qingyi Gu( )

1 edition published in 2019 in English and held by 1 WorldCat member library worldwide

In the context of biomass valorization by heterogeneous catalysis, computational chemistry is key to provide guidance to establish the nature of the active sites in combination with experimental characterizations. Then, the reaction mechanism can be studied to determine the rate determining transition state and intermediate and further design in silico better catalysts. We implemented this approach in several reactions involving alcohols that are key in the shift from a petroleum chemical feedstock to a biomass-based feedstock. Firstly, we focused on liquid phase alcohol oxidation by oxygen, a reaction that generally requires an alkaline environment, which is detrimental to the atom economy of the process since it generates the carboxylate salt instead of the carboxylic acid. We proposed a model of metal/basic water interface that includes the adsorption of hydroxide anion. It charges the metallic surface and modifies its catalytic activity. This model was first validated comparing the predicted activity of Au and Pt in presence and in absence of a base, and then used oxidation of alcohol ethoxylates by bimetals. Then, we switched to gas phase dehydration of C3 and C4 alcohols using phosphate-based catalysts. The modeling of the surfaces was based on experimental characterizations. The molecular coverage of water on the surface in function of the pressure and temperature was established using ab initio thermodynamic. The simulations of infrared spectra of CO, NH3 and C2H2 adsorption allowed us to identify the acido-basic sites which play an important role in the reaction mechanism investigation that followed
Biomass derivatives in heterogeneous catalysis : adsorption, reactivity and support from first principles by Romain Reocreux( )

1 edition published in 2017 in English and held by 1 WorldCat member library worldwide

Selective Alcohol Amination : theoretical Study for the Design of Innovative Heterogenerous Catalysts by Alexandre Dumon( )

1 edition published in 2016 in English and held by 1 WorldCat member library worldwide

Les polyamines sont des intermédiaires industriels très importants, cependant leur production dépend du pétrole, d'un apport en hydrogène et de produits toxiques (HCN, HCl). Il est donc important de changer de matière première. Dans cette optique, nous visons ici à aminer des alcools biosourcés. Nous avons donc réalisé des calculs DFT afin de comprendre les étapes clés de l'amination d'alcools, pour en maitriser les principes et résultats.En particulier, nous avons montré que l'environnement chimique jouait un grand rôle pendant cette réaction : expérimentalement, le Nickel (Ni) est plus actif que le Palladium (Pd). Cependant, les modèles de surfaces nues les prédisent aussi actifs. En prenant en compte un recouvrement de 1/9 monocouche en ammoniaque sur les surfaces, nous avons prédit une réactivité correcte : Ni plus actif que Pd.Nous avons aussi étudié les effets de l'environnement chimique sur l'hydrogénation de l'acide levulinique par l'acide formique, et sur l'isomérisation de l'isosorbide. Nous avons montré qu'il jouait un rôle sur la stabilité d'intermédiaires, modifiant l'activité des catalyseurs
Modélisation du comportement d'additifs aux interfaces pour guider la formulation de lubrifiants by Sarah Blanck( )

1 edition published in 2021 in French and held by 1 WorldCat member library worldwide

Heterogeneous catalysts for acceptor-less alcohol dehydrogenation - joined experimental and theoretical studies by Kamila Maria Kazmierczak( )

1 edition published in 2019 in English and held by 1 WorldCat member library worldwide

Acceptor-less alcohol dehydrogenation is a highly interesting reaction from the green chemistry point of view. In it, the (biomass derived) alcohols are transformed into carbonyl products, which are high value-added chemicals. Moreover, highly-energetic H2 in gaseous form is produced as the only by-product in the reaction. The presence of catalyst facilitates the process. Cobalt heterogeneous supported catalysts and unsupported shaped nanoparticles were investigated in this reaction. To understand their catalytic performance, the experimental and theoretical approaches were joined. Catalytic testing was aiming to assess the activity and selectivity of the catalysts, towards the dehydrogenation of mono- and polyalcohols (diols) possessing primary and secondary hydroxyl groups. Extensive characterization allowed to investigate the intrinsic properties of the materials. In between the reducibility of cobalt supported on materials of different nature was examined. For unsupported nanoparticles the shape, type of exposed metal facets, and also thickness of the ligand layer protecting the nanoparticles were analyzed. Density Functional Theory (DFT) calculations gave the opportunity to understand the catalytic behavior on the molecular level. The catalytic activity and selectivity, and the influence of the co-adsorbed ligands on the catalytic performance of metal, were studied for Co surfaces of different nature. By combining all the results it was possible to identify the factors guiding the catalyst activity
<> by Adrian Hühn( )

1 edition published in 2021 in English and held by 1 WorldCat member library worldwide

Hexafluoroisopropanol as a Versatile Solvent for Selective Catalytic Reactions of Alkenes to Amines by Gongming Peng( )

1 edition published in 2021 in English and held by 1 WorldCat member library worldwide

Synergie d'effets stériques, électroniques et bifonctionnels pour la conception de catalyseurs métalliques hautement sélectifs promus par des éléments non métalliques by Dan Wu( )

1 edition published in 2020 in English and held by 1 WorldCat member library worldwide

L'épuisement des ressources fossiles et les préoccupations environnementales croissantes encouragent la production de produits chimiques et de combustibles durables à partir des ressources de la biomasse. La sélectivité est le paramètre principal pour les processus catalytiques hétérogènes, en particulier pour la conversion catalytique de molécules à base de biomasse, qui sont enrichies en groupes fonctionnels et aboutissent à divers produits. Outre les propriétés intrinsèques telles que la phase active, la taille des particules, la morphologie et les interactions métal-support, récemment, une modification rationnelle vers la chimie de surface des catalyseurs métalliques a attiré une attention intensive pour les processus catalytiques sélectifs. Dans cette thèse, la modification de catalyseurs métalliques (Pd, Ru) avec divers promoteurs non métalliques (iode, brome et amines) et diverses stratégies (génération d'acidité in-situ, désactivation sélective, effet électronique et empreinte moléculaire) a été développée. Des réactions industrielles importantes telles que l'éthérification réductrice, l'hydrodésoxygénation, le clivage des composés modèles de la lignine et l'hydrogénation des aromatiques ont été étudiées.La modification du catalyseur Pd avec de l'iode et du brome a été étudiée dans le chapitre 3 ~ 4. Les relations structure-performance ont été étudiées par des réactions catalytiques et diverses caractérisations in-situ et ex-situ. Nous avons constaté que l'iode et le brome retirent des électrons du Pd, conduisant à des atomes d'iode et de brome chargés négativement sur la surface du Pd. La dissociation hétérolytique de l'hydrogène sur les sites Pd-I et Pd-Br conduit à la génération in-situ d'acidité de Brönsted. Les catalyseurs bifonctionnels acide-métal Pd-I et Pd-Br ont présenté une efficacité élevée pour l'éthérification réductrice d'aldéhydes avec de l'alcool et l'hydrodésoxygénation du 5-hydroxyméthylfurfural en diméthylfurane, respectivement.Au chapitre 5, la modification des catalyseurs métalliques avec des halogènes a été étendue au catalyseur Ru. Le catalyseur Ru-Br a démontré une sélectivité élevée pour le clivage du composé modèle de lignine diphényléther en mono-aromatiques. Des recherches plus poussées indiquent que les sites de terrasse sur les nanoparticules de Ru, qui sont responsables de l'hydrogénation des cycles aromatiques, sont sélectivement désactivés par les atomes de Br. De plus, les atomes de Br retirent des électrons de Ru, conduisant à des nanoparticules de Ru chargées positives. Les nanoparticules de Ru déficientes en électrons ont présenté une activité améliorée pour l'hydrogénolyse des liaisons C-O riches en électrons. La synergie de la désactivation sélective et de l'effet électronique a permis au catalyseur Ru-Br une efficacité élevée pour la production de phénol et de benzène à partir d'éther diphénylique avec une sélectivité élevée.Sur la base de la compréhension approfondie des effets multifonctionnels des modificateurs non métalliques sur les catalyseurs métalliques, une stratégie d'impression moléculaire a été proposée au chapitre 6. L'empreinte moléculaire pour la préparation d'un catalyseur hétérogène imprimé implique l'adsorption d'une molécule modèle, la désactivation avec des empoisonneurs avec réserve de îlots actifs non empoisonnés de forme et de taille prédéterminées pour la transformation sélective des molécules correspondant aux modèles. Nous démontrons cette stratégie d'hydrogénation sélective de molécules aromatiques avec différents radicaux alkyles par dépôt préliminaire de ces molécules comme matrice sur catalyseur Pd et désactivation à l'aide de diméthylaminopropylamine (DMAPA). La stratégie élaborée permet une application pratique pertinente à l'hydrogénation sélective et à l'élimination du benzène cancérigène du mélange d'aromatiques et peut être étendue pour l'amélioration de la sélectivité de nombreuses réactions catalytiques
Solvation and adsorptions at the solid / water interface : developments and applications by Paul Clabaut( )

1 edition published in 2021 in English and held by 1 WorldCat member library worldwide

This Ph.D. thesis investigates the impact of solvation on adsorption at the solid/water interfaceand presents method developments to unravel and realistically capture these effectsin theoretical studies.The SolvHybrid package was built to compute the solvation free energy difference betweena molecule solvated in bulk water and adsorbed at the Pt(111)/ water interface. SolvHybridis based on a hybrid QM/MM description and thermodynamic integration. The schemewas validated on experimentally available adsorption free energies of benzene and phenol.To increase the quality of its MM description and widen the applicability of SolvHybridbeyond the Pt(111)/water interface, forcefield developments have been pursued.The pairwise additive GAL19 forcefield was proposed to model water/noble-metal interactions.It demonstrated a great accuracy to reproduce the adsorption energy of a watermolecule on ten metallic (100) or (111) surface made of Cu, Ag, Au, Pd, Pt. This forcefield was later extended to more corrugated surfaces and nano-particles. To understandthe limitations of our pairwise additive force field for water layer structures, we also decomposedthe total interaction energy of water layers on metallic surfaces as computedby DFT. Apart from additive water/metal contributions, polarisation and charge-transferwere determined and quantified as major many-body effects, suggesting routes to secondgeneration forcefields.Metallic oxides were then investigated as a subsequent step in surface complexity, becauseof their tendency to react and even restructure in contact with water. Metadynamics waschosen to investigate the surface reconstruction of alumina in water. Our work demonstratedthe crucial role of the surface water structure in this process and its modificationin the presence of adsorbates. A panoply of methods (SolvHybrid, a GAL19-inspired forcefield,metadynamics, and thermodynamic integration) were then applied and comparedon the complex chemistry of the adsorption of ethanol on alumina in water, combining allprevious challenges
Réactivité catalytique à haut recouvrement : une approche théorique by Sarah Gautier( )

1 edition published in 2015 in English and held by 1 WorldCat member library worldwide

Petroleum industry has a strong interest in the selective hydrogenation of polyunsaturated hydrocarbons. This reaction is catalyzed by metallic particles or alloys and happens under pressure of hydrogen. In this work, we study the selective hydrogenation of butadiene into 1-butene, on two model catalysts which are Pt(111) and Sn/Pt-Pt(111). For this, we used the VASP code (Vienna Abinitio Simulation Package) that allows to perform periodic calculations in the framework of the Density Functional Theory (DFT). The choice of the catalysts was driven by the experimental and industrial communities who mostly use platinum because of its high activity, or alloys such as tin-platinum alloy, less active but more selective. Butadiene hydrogenation was already modeled in the past but only at T=0 K and without taking into account the real pressure conditions of the reactants. Our aim is to understand the impact of the reaction conditions which is why we ran this study at T and P conditions close to the one used experimentally, e.g. 300-400 K et 1-10 bar. For this, we setup a thermodynamic model to evaluate in a first step the surface composition when the reaction occurs. It came out that the most stable surface configuration corresponds to a coverage of 1 ML of hydrogen which suggests an Eley-Rideal type mechanism. Then we studied the kinetic aspect of this reaction and we calculated the hydrogenation pathways for different coverages of hydrogen. We concluded that there is a strong competition between the sensed mechanism, called Langmuir-Hinshelwood mechanism and implying strongly adsorbed species, and the Eley-Rideal mechanism, proposing a weak adsorption of one of the two reactants
Mechanisms and kinetics of alkenes isomerization and cracking in chabazite zeolite quantified by constrained ab initio molecular dynamics by Jérôme Rey( )

1 edition published in 2019 in English and held by 1 WorldCat member library worldwide

 
moreShow More Titles
fewerShow Fewer Titles
Audience Level
0
Audience Level
1
  General Special  
Audience level: 0.96 (from 0.94 for Heterogene ... to 0.97 for Heterogene ...)

Alternative Names
Carine Michel onderzoeker

Languages
English (12)

French (6)