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372 results on '"Payen, C."'

51. A magnetisation and Mössbauer study of triazole (M1−x2+Mx3+)M3+F5(Htaz)1−x(taz)x weberites (M = Fe, Co, Mn, Zn, Ga, V).

Author

Albino, M., Clark, L., Lhoste, J., Payen, C., Grenèche, J.-M., Lightfoot, P., Maisonneuve, V., and Leblanc, M.

Subjects
TRIAZOLES, WEBERITE, MAGNETIZATION
Abstract

A series of triazole fluoride weberites (M1−x2+Mx3+)M3+F5(Htaz)1−x(taz)x is obtained by hydrothermal synthesis. All phases are found to be isostructural to ZnAlF5(Htaz) by powder X-ray diffraction. Weberite structures are prone to induce the magnetic frustration of antiferromagnetic interactions originating from the cationic topology of HTB layers. The (nD) magnetic properties of (0D) Co–Ga, (1D) Zn–Fe, (3D) Fe–Ga, Mn–Fe, Co–Fe and Co–V couples are thus reported. Co2+ or Fe2+ magnetic anisotropy induces a negative magnetisation below TN and compensation temperatures for Mn–Fe and Co–Fe couples. All iron 3D magnetic phases exhibit high Néel temperatures, between 81 K and 102 K, and large ☋ϑP/TN☋ ratios, signalling strong magnetic frustration. Their cation site occupancies and the deduced (de)protonation states of the amine are accurately determined by 57Fe Mössbauer spectrometry. In addition, this spectroscopy evidences a subtle effect of the atmosphere that surrounds the samples: the magnetic ordering temperatures TN decrease significantly when the samples are cooled under vacuum with respect to samples that are cooled at ambient pressure. This novel phenomenon, which is highlighted for all studied (3D) triazole iron weberites, is reversible, and thus provides promising perspectives for understanding the underlying mechanism. [ABSTRACT FROM AUTHOR]

Published
2017
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52. Anomalous spectral weight in photoemission spectra of the hole-doped Haldane chain Y2-xSrxBaNiO5

Author

Fagot-Revurat, Y., Malterre, D., Lannuzel, F. X., Janod, E., Payen, C., Gavioli, L., and Bertran, F.

Subjects
Condensed Matter::Materials Science, Condensed Matter - Strongly Correlated Electrons, Strongly Correlated Electrons (cond-mat.str-el), Condensed Matter::Superconductivity, FOS: Physical sciences, Condensed Matter::Strongly Correlated Electrons, ELECTRONIC-STRUCTURE, INVERSE-PHOTOEMISSION, CRYSTAL-STRUCTURE, CHARGE DYNAMICS, SPIN DYNAMICS, Y2-XCAXBANIO5, Y2BANIO5, OXIDE, Settore FIS/03 - FISICA DELLA MATERIA
Abstract

In this paper, we present photoemission experiments on the hole doped Haldane chain compound $Y_{2-x}Sr_xBaNiO_5$. By using the photon energy dependence of the photoemission cross section, we identified the symmetry of the first ionisation states (d type). Hole doping in this system leads to a significant increase in the spectral weight at the top of the valence band without any change in the vicinity of the Fermi energy. This behavior, not observed in other charge transfer oxides at low doping level, could result from the inhomogeneous character of the doped system and from a Ni 3d-O 2p hybridization enhancement due to the shortening of the relevant Ni-O distance in the localized hole-doped regions., 5 pages, 4 figures

Published
2003

53. Thermally detected optical absorption, reflectance and photo-reflectance of In(As, P)/InP quantum wells grown by gas source molecular beam epitaxy

Author

Disseix, Pierre, Payen, C., Leymarie, Joël, Vasson, Aime, Mollot, F., Institut d’Électronique, de Microélectronique et de Nanotechnologie - UMR 8520 (IEMN), and Centrale Lille-Institut supérieur de l'électronique et du numérique (ISEN)-Université de Valenciennes et du Hainaut-Cambrésis (UVHC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Université Polytechnique Hauts-de-France (UPHF)

Published
2001

56. Spin dynamics, short-range order, and spin freezing in Y0.5Ca0.5BaCo4O7

Author

Stewart, J.R., Ehlers, G., Mutka, H., Fouquet, P., Payen, C., Lortz, Rolf Walter, Stewart, J.R., Ehlers, G., Mutka, H., Fouquet, P., Payen, C., and Lortz, Rolf Walter

Abstract

Y0.5Ca0.5BaCo4O7 was recently introduced as a possible candidate for capturing some of the predicted classical spin kagome ground-state features. Stimulated by this conjecture, we have taken up a more complete study of the spin correlations in this compound with neutron scattering methods on a powder sample characterized with high-resolution neutron diffraction and the temperature dependence of magnetic susceptibility and specific heat. We have found that the frustrated near-neighbor magnetic correlations involve not only the kagome planes but concern the full Co sublattice, as evidenced by the analysis of the wave-vector dependence of the short-range order. We conclude from our results that the magnetic moments are located on the Co sublattice as a whole and that correlations extend beyond the two-dimensional kagome planes. We identify intriguing dynamical properties, observing high-frequency fluctuations with a Lorentzian linewidth Γ⩽20 meV at ambient temperature. On cooling a low-frequency (~1 meV) dynamical component develops alongside the high-frequency fluctuations, which eventually becomes static at temperatures below T≈50 K. The high-frequency response with an overall linewidth of ~10 meV prevails at T⩽2 K, coincident with a fully elastic short-range-ordered contribution.

Published
2011

57. Control of codling moth Cydia pomonella L. with specific or selective methods

Author

Audemard, H., Sauphanor, Benoît, Franclet, J., Orts, R., Blanc, M., Martinet, C., Combe, Freddy, Payen, C., Welschen, P., Unité mixte de recherche Ecologie des invertébrés (UAPV), Institut National de la Recherche Agronomique (INRA)-Avignon Université (AU), Institut francilien recherche, innovation et société (IFRIS), and Institut National de la Recherche Agronomique (INRA)-École des hautes études en sciences sociales (EHESS)-OST-Université Paris-Est Marne-la-Vallée (UPEM)-Ministère de l'Education nationale, de l’Enseignement supérieur et de la Recherche (M.E.N.E.S.R.)-ESIEE Paris-Centre National de la Recherche Scientifique (CNRS)

Subjects
[SDV]Life Sciences [q-bio], ComputingMilieux_MISCELLANEOUS
Abstract

National audience

Published
1996

58. Lutte contre le carpocapse Cydia pomonella L

Author

Audemard, H., Sauphanor, Benoît, Franclet, J., Orts, R., Blanc, M., Martinet, C., Combe, Freddy, Payen, C., Welschen, P., ProdInra, Migration, Unité mixte de recherche Ecologie des invertébrés (UAPV), Institut National de la Recherche Agronomique (INRA)-Avignon Université (AU), Institut francilien recherche, innovation et société (IFRIS), and Institut National de la Recherche Agronomique (INRA)-École des hautes études en sciences sociales (EHESS)-OST-Université Paris-Est Marne-la-Vallée (UPEM)-Ministère de l'Education nationale, de l’Enseignement supérieur et de la Recherche (M.E.N.E.S.R.)-ESIEE Paris-Centre National de la Recherche Scientifique (CNRS)

Subjects
[SDV] Life Sciences [q-bio], [SDV]Life Sciences [q-bio]
Published
1996

59. Protection intégrée du verger de pommiers de l'an 2000. III Lutte contre le carpocapse Cydia pomonella L. Méthodes spécifiques ou sélectives

Author

Audemard, H., Sauphanor, Benoît, Franclet, J., Orts, R., Blanc, M., Martinet, C., Combe, Freddy, Payen, C., Welschen, P., Unité mixte de recherche Ecologie des invertébrés (UAPV), Institut National de la Recherche Agronomique (INRA)-Avignon Université (AU), Institut francilien recherche, innovation et société (IFRIS), Institut National de la Recherche Agronomique (INRA)-École des hautes études en sciences sociales (EHESS)-OST-Université Paris-Est Marne-la-Vallée (UPEM)-Ministère de l'Education nationale, de l’Enseignement supérieur et de la Recherche (M.E.N.E.S.R.)-ESIEE Paris-Centre National de la Recherche Scientifique (CNRS), and ProdInra, Migration

Subjects
[SDV] Life Sciences [q-bio], [SDV]Life Sciences [q-bio]
Abstract

no. hors série, collaboration INRA; National audience

Published
1996

63. On the electrochemical reactivity mechanism of CoSb3 vs. lithium

Author

Tarascon, J.M., Morcrette, M., Dupont, L., Chabre, Y., Payen, C., Larcher, D., Pralong, V., Tarascon, J.M., Morcrette, M., Dupont, L., Chabre, Y., Payen, C., Larcher, D., and Pralong, V.

Abstract

The electrochemical reactivity of CoSb3 vs. lithium has been studied. This phase reacts with more than 9.5 lithium in a two-step process, consisting of the uptake of 9 Li at a constant voltage close to 0.6 V, and of about one lithium over the final voltage decay to 0.01 V. Upon recharge, only 8 lithium can be extracted. From in situ X-ray diffraction, microscopy, and magnetic measurements, we provide evidence that the constant voltage process is rooted in the decomposition of CoSb3, leading to the formation of a composite made of Co and Li3Sb nanograins. We also illustrate that the mechanism by which the internal nanostructured (Co + Li3Sb) electrode, formed during reduction, converts back to CoSb3, is quite unusual. It involves, concomitant with the Li3Sb → Li2Sb → Sb dealloying reaction, a chemical reaction between Co and Sb nanograins. The extra capacity, measured at at low potential, appears to be nested in a decomposition-type reaction catalyzed by the cobalt nanoparticles, in a manner similar to that previously reported for CoO. Although these materials can reversibly uptake about 8 lithium, they are of negligible value, since their capacity rapidly decays with cycling, independent of the electrode processing.

Published
2003

64. Photoemission spectroscopy study of the hole-doped Haldane chain Y2-xSrxBaNiO5

Author

Fagot Revurat, Y, Malterre, D, Lannuzel, F, Janod, E, Payen, C, Gavioli, Luca, Bertran, F., Gavioli, Luca (ORCID:0000-0003-2782-7414), Fagot Revurat, Y, Malterre, D, Lannuzel, F, Janod, E, Payen, C, Gavioli, Luca, Bertran, F., and Gavioli, Luca (ORCID:0000-0003-2782-7414)

Abstract

In this paper, we present photoemission experiments on the hole-doped Haldane chain compound Y2-xSrxBaNiO5. By using the photon energy dependence of the photoemission cross section, we identified the symmetry of the first ionisation states (d type). Hole doping in this system leads to a significant increase in the spectral weight at the top of the valence band without any change in the vicinity of the Fermi energy. This behavior, never observed in other charge transfer oxides, could result from the Ni-3d-O-2P hybridization enhancement due to the shortening of the relevant Ni-O distance with doping. (C) 2002 Elsevier Science B.V. All rights reserved.

Published
2003

65. Anomalous spectral weight in photoemission spectra of the hole-doped Haldane chain Y2-xSrxBaNiO5

Author

Fagot Revurat, Y, Malterre, D, Lannuzel, F, Janod, E, Payen, C, Gavioli, Luca, Bertran, F., Gavioli, Luca (ORCID:0000-0003-2782-7414), Fagot Revurat, Y, Malterre, D, Lannuzel, F, Janod, E, Payen, C, Gavioli, Luca, Bertran, F., and Gavioli, Luca (ORCID:0000-0003-2782-7414)

Abstract

In this paper, we present photoemission experiments on the hole-doped Haldane chain compound Y2-xSrxBaNiO5. By using the photon-energy dependence of the photoemission cross section, we identified the symmetry of the first ionization states (d type). Hole doping in this system leads to a significant increase in the spectral weight at the top of the valence band without any change in the vicinity of the Fermi energy. This behavior, not observed in other charge-transfer oxides at low doping level, could result from the inhomogeneous character of the doped system and from a Ni 3d-O 2p hybridization enhancement due to the shortening of the relevant Ni-O distance in the localized hole-doped regions.

Published
2003

96. Myélome multiple familial: étude rétrospective de 18 familles

Author

Grosbois, B, primary, Altal, M, additional, Payen, C, additional, Fuzibet, JG, additional, Dorvaux, V, additional, Fabbro, M, additional, Facon, T, additional, Gaspard, MT, additional, Gilsan, B, additional, Lepeu, G, additional, Maigre, M, additional, Michaux, JL, additional, Pannelatti, G, additional, and Pierre, P, additional

Published
1998
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