Search

Your search keyword '"Grand Équipement National De Calcul Intensif, GENCI"' showing total 7 results
Start Over Author "Grand Équipement National De Calcul Intensif, GENCI"
7 results on '"Grand Équipement National De Calcul Intensif, GENCI"'

1. Hyperfine excitation of 13CCH and C13CH by collisions with para- H2

Author

Pirlot Jankowiak, P., Lique, F, Dagdigian, P J, Univ Rennes, CNRS, IPR (Institut de Physique de Rennes) –UMR 6251, F-35000 Rennes, France, Department of Chemistry, The Johns Hopkins University, Baltimore, MD 21218-2685, USA, Institut de Physique de Rennes (IPR), Université de Rennes (UR)-Centre National de la Recherche Scientifique (CNRS), Johns Hopkins University (JHU), TGCC, European Research Council, ERC, (811363), Commissariat à l'Énergie Atomique et aux Énergies Alternatives, CEA, and Grand Équipement National De Calcul Intensif, GENCI

Subjects
[PHYS]Physics [physics], molecular processes, molecular data -molecular processes -radiative transfer, molecular data, [PHYS.QPHY]Physics [physics]/Quantum Physics [quant-ph], radiative transfer, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
Abstract

International audience; The computation of hyperfine resolved cross sections and rate coefficients for open-shell molecules in collision with H2 is a true methodological and numerical challenge. Such collisional data are however required to interpret astrophysical observations. We report the first hyperfine resolved rate coefficients for (de-)excitation of 13CCH and C13CH isotopologues induced by collisions with para-H2. These calculations have been performed using a recently published C2H-H2 potential energy surface. Hyperfine resolved cross sections and rate coefficients between the first 98 energy levels of the two isotopologues were determined using a recoupling technique for temperatures ranging from 5 to 100 K. Significant isotopic substitution effects were found, showing the necessity of computing isotopologue specific collisional data. These rate coefficents have then been used in a simple radiative transfer modelling for typical molecular cloud conditions. © 2023 The Author(s) Published by Oxford University Press on behalf of Royal Astronomical Society.

Published
2023

2. The excitation of CO in CO-dominated cometary comae

Author

M Żółtowski, F Lique, J Loreau, A Faure, M Cordiner, Institut de Physique de Rennes (IPR), Université de Rennes (UR)-Centre National de la Recherche Scientifique (CNRS), Catholic University of Leuven - Katholieke Universiteit Leuven (KU Leuven), Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Centre National d'Études Spatiales [Toulouse] (CNES)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France -Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France, National Aeronautics and Space Administration (NASA), Catholic University of America, National Science Foundation, NSF: AST-2009253, KU Leuven: 19-00313, Commissariat à l'Énergie Atomique et aux Énergies Alternatives, CEA, Grand Équipement National De Calcul Intensif, GENCI: A0110413001, and Wroclawskie Centrum Sieciowo-Superkomputerowe, Politechnika Wroclawska, WCSS

Subjects
[PHYS]Physics [physics], molecular data, Space and Planetary Science, comets: general, scattering, Astronomy and Astrophysics, Quantum dynamics, Molecular physics, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
Abstract

International audience; An abundance of CO significantly surpassing the abundance of H2O is observed in the comae of comets at large heliocentric distances. In these environments, CO molecules can be the most abundant species and they may be therefore the dominant projectiles inducing collisional excitation of the cometary molecules. It is thus of high interest to investigate the excitation of CO by CO. This article provides a new set of CO–CO collisional rate coefficients for temperatures up to 150 K and for CO rotational levels j1 up to 10. These data are obtained from quantum scattering calculations using the coupled states approximation. They are used in a simple radiative transfer model in order to test their impact on the excitation of cometary CO. Because mutual (de-)excitations of the target and projectile are important, the CO projectile was assumed to be thermalized at the kinetic temperature. We found that the non-local thermodynamical equilibrium regime extends for CO densities in the range 103–107 cm−3. We also observed that as soon as the CO/H2O ratio is larger than 70 per cent/30 per cent, the contribution of H2O collisions can be neglected. Similarly, the excitation of CO by CO may be ignored for relatively low CO/H2O density ratios (≤30 per cent/70 per cent). Finally, when the coma is a ∼50 per cent/50 per cent mixture of CO and H2O, the contribution of both colliders is similar and has to be considered. © 2023 The Author(s) Published by Oxford University Press on behalf of Royal Astronomical Society.

Published
2023

3. Ventilation Changes Drive Orbital-Scale Deoxygenation Trends in the Late Cretaceous Ocean

Author

A.‐C. Sarr, Y. Donnadieu, M. Laugié, J.‐B. Ladant, B. Suchéras‐Marx, F. Raisson, Centre européen de recherche et d'enseignement des géosciences de l'environnement (CEREGE), Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), TotalEnergies, 2019-A0050102212, 2020-A0090102212, 2021-A0110102212, Grand Équipement National De Calcul Intensif, GENCI, and The authors acknowledge Olivier Aumont, Christian Ethé and Laurent Bopp for their contribution to the development of the adapted version of the PISCES code for deep-time simulations. The authors thank the CEA/CCRT for providing access to the HPC resources of TGCC under the allocation 2019-A0050102212, 2020-A0090102212 and 2021-A0110102212 made by GENCI. The authors thank TotalEnergies for funding the project and granting permission to publish. The authors are also grateful to David de Vleeschouwer and Michel Crucifix for their comments and reviews.

Subjects
Geophysics, [SDU]Sciences of the Universe [physics], General Earth and Planetary Sciences
Abstract

International audience; Mechanisms that drive cyclicity in marine sediment deposits during hothouse climate periods in response to Earth's orbit variations remain debated. Orbital cycles fingerprint in the oceanographic records results from the combined effect of terrestrial (e.g., Weathering derived nutrient supply, freshwater discharge) and oceanic (e.g., productivity, oxygenation) processes, whose respective contribution remains to be clarified. Here we investigate the effect of extreme orbital configurations on the oxygenation state of the ocean using marine biogeochemistry simulations with the IPSL-CM5A2 Earth System Model under Cenomanian-Turonian boundary conditions. Our simulations show that small changes in ocean ventilation triggered by orbitally induced variations in deep water formation have a strong impact on the spatial distribution of dissolved oxygen. This phenomena is amplified in enclosed and already poorly oxygenated basins, such as the proto-Atlantic ocean, where up to 50% of the water volume become anoxic for some of the configurations.

Published
2022

4. Climate benefit of a future hydrogen economy

Author

Didier Hauglustaine, Fabien Paulot, William Collins, Richard Derwent, Maria Sand, Olivier Boucher, Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Institut Pierre-Simon-Laplace (IPSL (FR_636)), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), 2021-39, Norges Forskningsråd: 320240, Grand Équipement National De Calcul Intensif, GENCI: gen2201, and The authors would like to thank the three anonymous reviewers for their insightful comments which improved the manuscript. We thank G. Myhre, M. Prather, K. Shine, and D. Stevenson for helpful discussions. This study was partly funded by the Research Council of Norway under project No. 320240 'HYDROGEN: Climate and environmental impacts of hydrogen emissions' and by the Direction Générale de l’Aviation Civile (DGAC) under the 'Climaviation' project (DGAC agreement N°2021-39). The simulations were performed using HPC resources from GENCI (Grand Equipement National de Calcul Intensif) under project gen2201.

Subjects
[SDU]Sciences of the Universe [physics], General Earth and Planetary Sciences, hydrogen economy, hydrogen transition, General Environmental Science, Hydrogen
Abstract

Hydrogen is recognised as an important future energy vector for applications in many sectors. Hydrogen is an indirect climate gas which induces perturbations of methane, ozone, and stratospheric water vapour, three potent greenhouse gases. Using data from a state-of-the-art global numerical model, here we calculate the hydrogen climate metrics as a function of the considered time-horizon and derive a 100-year Global Warming Potential of 12.8 ± 5.2 and a 20-year Global Warming Potential of 40.1 ± 24.1. The considered scenarios for a future hydrogen transition show that a green hydrogen economy is beneficial in terms of mitigated carbon dioxide emissions for all policy-relevant time-horizons and leakage rates. In contrast, the carbon dioxide and methane emissions associated with blue hydrogen reduce the benefit of a hydrogen economy and lead to a climate penalty at high leakage rate or blue hydrogen share. The leakage rate and the hydrogen production pathways are key leverages to reach a clear climate benefit from a large-scale transition to a hydrogen economy.

Published
2022

5. Light-activated interlayer contraction leads to high-efficiency in 2D perovskite solarcells

Author

Traoré, Boubacar, Li, Wenbin, Sidhik, Siraj, Asadpour, Reza, Hou, Jin, Zhang, Hao, Fehr, Austin, Essman, Joseph, Wang, Yafei, Hoffman, Justin, Spanopoulos, Ioannis, Crochet, Jared, Tsai, Esther, Strzalka, Joseph, Alam, Muhammad, Kanatzidis, Mercouri, Katan, Claudine, Blancon, Jean Christophe, Mohite, Aditya, Even, Jacky, Institut des Sciences Chimiques de Rennes (ISCR), Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Rice University [Houston], Purdue University [West Lafayette], Northwestern University [Evanston], Los Alamos National Laboratory (LANL), Brookhaven National Laboratory [Upton, NY] (BNL), UT-Battelle, LLC-Stony Brook University [SUNY] (SBU), State University of New York (SUNY)-State University of New York (SUNY)-U.S. Department of Energy [Washington] (DOE), Argonne National Laboratory [Lemont] (ANL), Institut des Fonctions Optiques pour les Technologies de l'informatiON (Institut FOTON), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-École Nationale Supérieure des Sciences Appliquées et de Technologie (ENSSAT)-Centre National de la Recherche Scientifique (CNRS), J. Even acknowledges the financial support from the Institut Universitaire de France. DFT calculations were performed at Institut FOTON as well as Institut des Sciences Chimiques de Rennes, and the work was granted access to the HPC resources of Très Grand Centre de Calcul du CEA (TGCC), the Centre Informatique National de I’Enseignement Supérieur (CINES) and Institut du développement et des ressources en informatique scientifique (IDRIS) under allocations 2019-A0060906724 and 2019-A0070907682 made by Grand Équipement National de Calcul Intensif (GENCI)., CNRS Israeli French scientific cooperation (Joint Research Projects 2019-2021 ALLPOA)., European Project: PeroCUBE, Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA), U.S. Department of Energy [Washington] (DOE)-UT-Battelle, LLC-Stony Brook University [SUNY] (SBU), State University of New York (SUNY)-State University of New York (SUNY), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-École Nationale Supérieure des Sciences Appliquées et de Technologie (ENSSAT)-Centre National de la Recherche Scientifique (CNRS)-IMT Atlantique Bretagne-Pays de la Loire (IMT Atlantique), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT), even, jacky, and High-Performance Large Area Organic Perovskite devices for lighting, energy and Pervasive Communications - PeroCUBE - INCOMING

Subjects
[PHYS]Physics [physics], [CHIM] Chemical Sciences, [CHIM]Chemical Sciences, [PHYS] Physics [physics]
Abstract

National audience; Despite their improved stability and versatility, 2D layered perovskites’ solar cell efficiencies lag behind those of their 3D counterparts, which currently exceed 25%. Through a proper selection of the organic spacer, 2D perovskites can be synthetized in different configurations adopting various phases such as the Ruddlesden-Popper (RP), the Alternating Cation Interlayer (ACI) or the Dion-Jacobson ones. Tailoring the organic spacer type has been shown to enhance the electronic coupling along the layered perovskite stacking axis and thereby enhance carrier transport resulting in improved efficiencies.

Published
2021

6. Electronic interaction between two fluorenyl-bridged molybdenocene dithiolene electroactive centers

Author

Youssef, K., Vacher, Antoine, Barriere, F, Roisnel, T., Lorcy, Dominique, Institut des Sciences Chimiques de Rennes (ISCR), Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), 19-CE08-0029-02, Agence Nationale de la Recherche, ANR, Grand Équipement National De Calcul Intensif, GENCI, and ANR-19-CE08-0029,THIOMOFS,chalcogénures hybrides multi-redox et poreux(2019)

Subjects
Inorganic Chemistry, Electrostatic interactions, History, Bimetallic, Dithiolene, Polymers and Plastics, Materials Chemistry, Molybdenocene, [CHIM]Chemical Sciences, Business and International Management, Physical and Theoretical Chemistry, Industrial and Manufacturing Engineering, Electronic coupling
Abstract

International audience; A bimetallic metal complex involving a fluorene linker between two redox active bis(cyclopentadienyl)molybdenum dithiolene moieties has been synthesized and characterized by electrochemistry and spectroelectrochemistry. Cyclic voltammetry experiments show sequential oxidation of the two redox centers with small ΔE values between the first and the second redox processes and between the third and the fourth ones. Comparative electrochemical studies carried out using either [NBu4][PF6] or the poorly coordinating supporting electrolyte [Na][B(C6H4(CF3)2)4] in dichloromethane indicate strong electrostatic effects on consecutive electron transfers, especially for highly charged species. Spectroelectrochemical investigations together with DFT calculations evidence that the two molybdenocene dithiolene electrophores are weakly electronically coupled through the organic bridge. © 2022 Elsevier Ltd

Published
2022

7. Fully self-consistent calculations of momentum distributions of annihilating electron-positron pairs in SiC

Author

Marie-France Barthe, Julia Wiktor, Gérald Jomard, Marc Torrent, Marjorie Bertolus, Département d'Etudes des Combustibles (DEC), CEA-Direction de l'Energie Nucléaire (CEA-DEN), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), DAM Île-de-France (DAM/DIF), Direction des Applications Militaires (DAM), Conditions Extrêmes et Matériaux : Haute Température et Irradiation (CEMHTI), Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), This work was partly performed using high-performance computing resources from Le Centre de calcul recherche et technologie of the Grand équipement national de calcul intensif (GENCI-CCRT) (Grant No. x2015096008) and was supported by the French program Nucléaire, Energie, Environnement, Déchets et Société (NEEDS)., CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), and Université d'Orléans (UO)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Physics, 02 engineering and technology, Electron, [CHIM.MATE]Chemical Sciences/Material chemistry, 021001 nanoscience & nanotechnology, 01 natural sciences, Spectral line, Momentum, Positron, Vacancy defect, 0103 physical sciences, Annihilation radiation, Density functional theory, Atomic physics, 010306 general physics, 0210 nano-technology, Wave function
Abstract

International audience; We performed calculations of momentum distributions of annihilating electron-positron pairs in various fully relaxed vacancy defects in SiC. We used self-consistent two-component density functional theory schemes to find the electronic and positronic densities and wave functions in the considered systems. Using the one-dimensional momentum distributions (Doppler-broadened annihilation radiation line shapes) we calculated the line-shape parameters S and W. We emphasize the effect of the experimental resolution and the choice of the integration ranges for the S and W parameters on the distributions of the points corresponding to different defects in the S(W) plot. We performed calculation for two polytypes of SiC, 3C, and 6H and showed that for silicon vacancies and clusters containing this defect there were no significant differences between the Doppler spectra. The results of the Doppler spectra calculations were compared with experimental data obtained for n-type 6H-SiC samples irradiated with 4-MeV Au ions. We observed a good general agreement between the measured and calculated points

Published
2016

Catalog

Books, media, physical & digital resources
See catalog results