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Salles F, Jobic H, Maurin G, Koza MM, Llewellyn PL, Devic T, Serre C, Ferey G. Experimental evidence supported by simulations of a very high H2 diffusion in metal organic framework materials. PHYSICAL REVIEW LETTERS 2008; 100:245901. [PMID: 18643600 DOI: 10.1103/physrevlett.100.245901] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2008] [Indexed: 05/26/2023]
Abstract
Quasielastic neutron scattering measurements are combined with molecular dynamics simulations to extract the self-diffusion coefficient of hydrogen in the metal organic frameworks MIL-47(V) and MIL-53(Cr). We find that the diffusivity of hydrogen at low loading is about 2 orders of magnitude higher than in zeolites. Such a high mobility has never been experimentally observed before in any nanoporous materials, although it was predicted in carbon nanotubes. Either 1D or 3D diffusion mechanisms are elucidated depending on the chemical features of the MIL framework.
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Maurin G, Llewellyn P, Poyet T, Kuchta B. Influence of extra-framework cations on the adsorption properties of X-faujasite systems: microcalorimetry and molecular simulations. J Phys Chem B 2007; 109:125-9. [PMID: 16850994 DOI: 10.1021/jp0461753] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Isotherms and differential enthalpies of adsorption are obtained for nitrogen at ambient temperature on monovalent (Li(+), Na(+), K(+)) and divalent (Ca(2+), Ba(2+), Sr(2+), Mn(2+)) substituted X-faujasite systems by microcalorimetry measurements. These experimental data are compared with those obtained by combining grand canonical Monte Carlo simulations and newly derived force fields for describing the interactions between the extra-framework cations and the adsorbates obtained from a simple model based only on the intrinsic properties of the cations. It is the first time that such good qualitative agreement is reported between experiment and simulation for a series of both monovalent and divalent cations.
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Douillard JM, Maurin G, Henn F, Devautour-Vinot S, Giuntini JC. Use of dielectric relaxation for measurements of surface energy variations during adsorption of water on mordenite. J Colloid Interface Sci 2007; 306:440-8. [PMID: 17126849 DOI: 10.1016/j.jcis.2006.09.067] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2006] [Revised: 09/22/2006] [Accepted: 09/22/2006] [Indexed: 10/23/2022]
Abstract
This paper tries to assess simply and quantitatively the link between classical adsorption theories and dielectric spectroscopy, in order to demonstrate that dielectric spectroscopy can be used as a tool of determination of surface energy variations due to movements of charge carriers at the surface of solids. A simple theory is developed to analyze hops of cations at the surface of mordenite, which are detected by complex impedance spectroscopy during adsorption of water. An energy of extraction of the cation can be determined from measurements and its dependence on the quantity of water molecules adsorbed is shown and qualitatively and quantitatively explained, using relationships developed in order to interpret adsorption phenomena generally. The agreement with other determinations of the adsorption energies and solid surface energy is correct.
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Déroche I, Maurin G, Llewellyn P, Castro M, Wright P, Bejblova M, Cejka J. A computational study of the stretching frequencies of Brønsted acid sites in SAPO STA-7: preliminary comparison with infrared. ACTA ACUST UNITED AC 2007. [DOI: 10.1016/s0167-2991(07)81044-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/07/2023]
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Ramsahye NA, Maurin G, Bourrelly S, Llewellyn P, Loiseau T, Ferey G. Charge distribution in metal organic framework materials: transferability to a preliminary molecular simulation study of the CO2adsorption in the MIL-53 (Al) system. Phys Chem Chem Phys 2007; 9:1059-63. [PMID: 17311147 DOI: 10.1039/b613378a] [Citation(s) in RCA: 106] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Density functional theory calculations have been performed in order to extract the charge distribution in the aluminium-containing MIL-53 structure, to allow further computational studies of adsorption in these materials. Both cluster and periodic methods have been used and the charges calculated for each atom constituting the organic and inorganic part of the material, were discussed. Preliminary grand canonical Monte Carlo simulations, based on a consistent set of potential parameters and this newly derived charge distribution, predicted for enthalpies of adsorption for CO(2) at low coverage in the "large" and "narrow" pore versions of MIL-53 (Al) to be significantly different. These calculated enthalpies reproduced the two distinct ranges of values observed by microcalorimetry on either side of 6 bars quite well. This agreement between experiment and simulation validated our previous assumption, suggesting a structural switching of the hybrid material during the adsorption process. The microscopic mode of interaction between the hybrid porous framework and the CO(2) adsorption was then carefully analysed in both of the MIL-53 (Al) structures.
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Aharonian F, Akhperjanian AG, Bazer-Bachi AR, Beilicke M, Benbow W, Berge D, Bernlöhr K, Boisson C, Bolz O, Borrel V, Braun I, Brown AM, Bühler R, Büsching I, Carrigan S, Chadwick PM, Chounet LM, Coignet G, Cornils R, Costamante L, Degrange B, Dickinson HJ, Djannati-Ataï A, Drury LO, Dubus G, Egberts K, Emmanoulopoulos D, Espigat P, Feinstein F, Ferrero E, Fiasson A, Fontaine G, Funk S, Funk S, Füßling M, Gallant YA, Giebels B, Glicenstein JF, Goret P, Hadjichristidis C, Hauser D, Hauser M, Heinzelmann G, Henri G, Hermann G, Hinton JA, Hoffmann A, Hofmann W, Holleran M, Hoppe S, Horns D, Jacholkowska A, de Jager OC, Kendziorra E, Kerschhaggl M, Khélifi B, Komin N, Konopelko A, Kosack K, Lamanna G, Latham IJ, Le Gallou R, Lemière A, Lemoine-Goumard M, Lenain JP, Lohse T, Martin JM, Martineau-Huynh O, Marcowith A, Masterson C, Maurin G, McComb TJL, Moulin E, de Naurois M, Nedbal D, Nolan SJ, Noutsos A, Orford KJ, Osborne JL, Ouchrif M, Panter M, Pelletier G, Pita S, Pühlhofer G, Punch M, Ranchon S, Raubenheimer BC, Raue M, Rayner SM, Reimer A, Ripken J, Rob L, Rolland L, Rosier-Lees S, Rowell G, Sahakian V, Santangelo A, Saugé L, Schlenker S, Schlickeiser R, Schröder R, Schwanke U, Schwarzburg S, Schwemmer S, Shalchi A, Sol H, Spangler D, Spanier F, Steenkamp R, Stegmann C, Superina G, Tam PH, Tavernet JP, Terrier R, Tluczykont M, van Eldik C, Vasileiadis G, Venter C, Vialle JP, Vincent P, Völk HJ, Wagner SJ, Ward M. Fast Variability of TeraElectron Volt γ Rays from the Radio Galaxy M87. Science 2006; 314:1424-7. [PMID: 17068224 DOI: 10.1126/science.1134408] [Citation(s) in RCA: 241] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
The detection of fast variations of the tera-electron volt (TeV) (10(12) eV) gamma-ray flux, on time scales of days, from the nearby radio galaxy M87 is reported. These variations are about 10 times as fast as those observed in any other wave band and imply a very compact emission region with a dimension similar to the Schwarzschild radius of the central black hole. We thus can exclude several other sites and processes of the gamma-ray production. The observations confirm that TeV gamma rays are emitted by extragalactic sources other than blazars, where jets are not relativistically beamed toward the observer.
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Maurin G, Plant DF, Henn F, Bell RG. Cation Migration upon Adsorption of Methanol in NaY and NaX Faujasite Systems: A Molecular Dynamics Approach. J Phys Chem B 2006; 110:18447-54. [PMID: 16970470 DOI: 10.1021/jp062059j] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Molecular dynamics simulations have been carried out to address the question of cation migration upon adsorption of methanol in NaY and NaX faujasite systems as a function of the loading. For NaY, it has been shown that, at low and intermediate loadings, SII cations can migrate toward the center of the supercage due to strong interactions with the adsorbates, followed by a hopping of SI' from the sodalite cage into the supercage to fill the vacant SII site. A SI' cation can also migrate across the double six ring and takes a SI' vacant position. SI cations mainly remain trapped in their initial sites whatever the loading. At high loading, only limited motions are observed for SII cations due to steric effects induced by the presence of adsorbates within the supercage. For NaX, the SIII' cations which occupy the most accessible adsorption sites are significantly moving upon coordination to the methanol molecules; the extent of this mobility exhibits a maximum for 48 methanol molecules per unit cell before decreasing at higher loadings due to steric hindrance. In addition, the SI' and SII cations remain almost trapped in their initial sites whatever the loading. Indeed, the most probable migration mechanism involves SIII' cation displacements into nearby SIII' sites.
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Plant DF, Maurin G, Bell RG. Modeling the Concentration Dependence of the Methanol Self-Diffusivity in Faujasite Systems: Comparison with the Liquid Phase. J Phys Chem B 2006; 110:15926-31. [PMID: 16898746 DOI: 10.1021/jp0629543] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Molecular dynamics simulations were performed to understand further the concentration dependence of the self-diffusion of methanol in the faujasite zeolite systems. The evolution of the self-diffusivity was investigated as a function of coverage for DAY and NaY systems to study the effect of both the pore confinement and the presence of the extraframework cations within the supercage. It was found that the self-diffusivity decreases with loading for DAY, whereas for NaY it passes through a maximum at intermediate coverage, in agreement with pulse-field gradient NMR and quasi elastic neutron scattering data reported in similar systems. The activation energies of the methanol diffusion corresponding to a combination of both intra- and intercage motions were evaluated as a function of the coverage. The simulated trends are interpreted on the basis of the predominant interactions which take place in both systems. Finally, the preferential arrangement of the adsorbate molecules are provided and compared with those simulated in the liquid phase. For the fully loaded materials, it was seen that the methanol molecules form a one-dimensional hydrogen-bonded chain along the channels in DAY whereas only dimers are present in NaY.
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Plant DF, Maurin G, Jobic H, Llewellyn PL. Molecular Dynamics Simulation of the Cation Motion upon Adsorption of CO2 in Faujasite Zeolite Systems. J Phys Chem B 2006; 110:14372-8. [PMID: 16854144 DOI: 10.1021/jp062381u] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Molecular Dynamics simulations have been carried out in NaX and NaY Faujasite systems to deepen understanding of the cation rearrangement during the CO2 adsorption process suggested by our recent diffusivity measurements. This study is a major contribution since the rearrangement of the cations in Faujasite, the most promising adsorbent for CO2 storage, can represent a significant breakthrough in understanding the adsorption and diffusion processes at the mircroscopic scale. For NaY, it has been shown that at low and intermediate loadings, SII cations can migrate toward the center of the supercage due to strong interactions with the adsorbates, followed by a hopping of SI'cation from the sodalite cage into the supercage to fill the vacant SII site. The SI cations are only displaced at a higher loading, leading to cation de-trapping out of the double six rings into the vacant SI' sites. For NaX, the SIII' cations which occupy the most accessible adsorption sites move significantly upon coordination to the carbon dioxide molecules. The SI' and SII cations remain consistently located in their initial sites whatever the loading. Indeed, the most probable migration mechanism involves SIII' cation displacements into nearby vacant SIII' sites.
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Gabrielli C, Maurin G, Mirkova L, Perrot H. Transfer function analysis of hydrogen permeation through a metallic membrane in a Devanathan cell. J Electroanal Chem (Lausanne) 2006. [DOI: 10.1016/j.jelechem.2006.01.030] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Gabrielli C, Maurin G, Mirkova L, Perrot H, Tribollet B. Transfer function analysis of hydrogen permeation through a metallic membrane in a Devanathan cell. I. Theory. J Electroanal Chem (Lausanne) 2006. [DOI: 10.1016/j.jelechem.2006.01.029] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Maurin G, Llewellyn PL, Bell RG. Adsorption Mechanism of Carbon Dioxide in Faujasites: Grand Canonical Monte Carlo Simulations and Microcalorimetry Measurements. J Phys Chem B 2005; 109:16084-91. [PMID: 16853044 DOI: 10.1021/jp052716s] [Citation(s) in RCA: 81] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Molecular simulations have been coupled with adsorption microcalorimetry measurements in order to understand more deeply the interactions between carbon dioxide and various types of faujasite surfaces. The modeling studies, based on newly derived interatomic potentials for describing the interactions within the whole system, provide isotherms and evolutions of the differential enthalpy of adsorption as a function of coverage for DAY, NaY, and NaLSX which are in very good accordance with those obtained experimentally. The microscopic mechanism of CO2 adsorption was carefully analyzed, with different behaviors proposed, depending on the energetic characteristics of each faujasite surface, which are consistent with the trends observed for the differential enthalpies of adsorption.
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Varvara S, Muresan L, Popescu IC, Maurin G. Comparative study of copper electrodeposition from sulphate acidic electrolytes in the presence of IT-85 and of its components. J APPL ELECTROCHEM 2005. [DOI: 10.1007/s10800-004-2398-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Bourrelly S, Maurin G, Llewellyn P. Adsorption microcalorimetry of methane and carbon dioxide on various zeolites. ACTA ACUST UNITED AC 2005. [DOI: 10.1016/s0167-2991(05)80456-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/07/2023]
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Henn F, Devautour-Vinot S, Giuntini JC, Maurin G. Alkali Metal Bonding Energy and Activation Energy for dc Conductivity in Porous and Glassy Solid Oxides. J Phys Chem B 2004. [DOI: 10.1021/jp049802x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Maurin G, Bell R, Senet P, Devautour-Vinot S. Static and Dynamic Properties of the Nonframework Cations in Na-Mordenites Zeolite. MOLECULAR SIMULATION 2004. [DOI: 10.1080/08927020410001717236] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Maurin G, Bell RG, Devautour S, Henn F, Giuntini JC. Modeling the Effect of Hydration in Zeolite Na+−Mordenite. J Phys Chem B 2004. [DOI: 10.1021/jp034151a] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Maurin G, Bell RG, Devautour S, Henn F, Giuntini JC. Theoretical prediction of low-frequency vibrations of extra-framework cations in mordenite zeolites. Phys Chem Chem Phys 2004. [DOI: 10.1039/b311655g] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Devillers J, Decourtye A, Budzinskid H, Pham-Delègue MH, Cluzeau S, Maurin G. Comparative toxicity and hazards of pesticides to Apis and non-Apis bees. A chemometrical study. SAR AND QSAR IN ENVIRONMENTAL RESEARCH 2003; 14:389-403. [PMID: 14758982 DOI: 10.1080/10629360310001623980] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
The adverse effects of 158 pesticides to the Honey bee (Apis mellifera), the alfalfa leafcutting bee (Megachile rotundata) and the alkali bee (Nomia melanderi) were compared by means of various linear and non-linear multivariate analyses. A comparison exercise including the bumble bee (Bombus spp.) was also performed from a more restricted set of 32 pesticides. While no difference of sensitivity was found between A. mellifera and Bombus spp., M. rotundata appeared the most susceptible to pesticides followed by N. melanderi.
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Gabrielli C, Maurin G, Perrot H, Poindessous G, Rosset R. Investigation of electrochemical calcareous scaling. J Electroanal Chem (Lausanne) 2002. [DOI: 10.1016/s0022-0728(02)01044-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Devillers J, Pham-Delègue MH, Decourtye A, Budzinski H, Cluzeau S, Maurin G. Structure-toxicity modeling of pesticides to honey bees. SAR AND QSAR IN ENVIRONMENTAL RESEARCH 2002; 13:641-648. [PMID: 12570042 DOI: 10.1080/1062936021000043391] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
A quantitative structure-activity relationship (QSAR) model was derived for estimating the acute toxicity of pesticides on the honey bee. Chemicals were described by means of autocorrelation descriptors encoding lipophilicity (H), molar refractivity (MR) and the H-bonding acceptor ability (HBA) of the pesticides. A three-layer feedforward neural network trained by the back-propagation algorithm was used as statistical engine for deriving a powerful QSAR model. The root mean square residual (RMSR) values for the training and testing sets were 0.430 and 0.386, respectively. The practical interest of this original model was discussed.
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Maurin G, Devautour S, Henn F, Giuntini JC, Senet P. Activated cation motions in zeolites. J Chem Phys 2002. [DOI: 10.1063/1.1494425] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Cachet C, Ganne F, Maurin G, Petitjean J, Vivier V, Wiart R. EIS investigation of zinc dissolution in aerated sulfate medium. Part I: bulk zinc. Electrochim Acta 2001. [DOI: 10.1016/s0013-4686(01)00740-x] [Citation(s) in RCA: 81] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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