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J.-m. Mestdagh - One of the best experts on this subject based on the ideXlab platform.
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multipronged mapping to the dynamics of a Barium Atom deposited on argon clusters
Physical Chemistry Chemical Physics, 2016Co-Authors: S Awali, M. Briant, M.-a. Gaveau, J.-m. Mestdagh, B Soep, O Gobert, R Maksimenka, Lionel PoissonAbstract:The dynamics of an electronically excited Barium Atom deposited at the surface of an Ar≈500 cluster was explored in a multipronged approach which associates information from frequency-resolved nanosecond experiments and information from femtosecond time-resolved experiments. In both types of experiments, the dynamics is monitored by photoelectron and photoion spectroscopy.
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multipronged mapping to the dynamics of a Barium Atom deposited on argon clusters supplementary material
2016Co-Authors: S Awali, M. Briant, M.-a. Gaveau, J.-m. Mestdagh, B Soep, O Gobert, R Maksimenka, Lionel PoissonAbstract:The dynamics of an electronically excited Barium Atom deposited at the surface of an Ar≈500 cluster was explored in a multipronged approach which associates information from frequency-resolved nanosecond experiments and information from femtosecond time-resolved experiments. In both types of experiments, the dynamics is monitored by photoelectron and photoion spectroscopy.
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Observation of a Barium xenon exciplex within a large argon cluster
Journal of Chemical Physics, 2010Co-Authors: M. Briant, M.-a. Gaveau, J.-m. MestdaghAbstract:Spectroscopic measurements provide fluorescence and excitation spectra of a single Barium Atom codeposited with xenon Atoms on argon clusters of average size ≈ 2000. The spectra are studied as a function of the number of xenon Atoms per cluster. The excitation spectrum with ∼ 10 xenon Atoms per cluster is qualitatively similar to that observed when no xenon Atom is present on the cluster. It consists of two bands located on each side of the 6s6p 1P−6s2 1S resonance line of the free Barium. In contrast, the fluorescence spectrum differs qualitatively since a Barium-xenon exciplex is observed, which has no counterpart in xenon free clusters. In particular an emission is observed, which is redshifted by 729 cm−1 with respect to the Ba(6s6p 1P−6s2 1S) resonance line.
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Cluster isolated chemical reaction (CICR) spectroscopy: Ba Atoms and Ba(CH4)n complexes on large neon clusters
The Journal of Chemical Physics, 2000Co-Authors: M. Briant, M.-a. Gaveau, J.-m. Mestdagh, J. P. VisticotAbstract:The cluster isolated chemical reaction (CICR) technique was applied to neon clusters (Ne≈7000) on which Barium Atoms and methane molecules were deposited. Clusters carrying Barium only were studied first. Qualitatively, the present results on neon clusters are in line with our previous results on argon clusters. In particular, surface location of Barium was observed. The central part of the present work concerns neon clusters carrying both one Barium Atom and one to ten methane molecules. Several types of spectroscopy were performed in the region of the resonance transition (6s2)1S→(6s6p)1P of Barium (excitation spectrum of the total fluorescence, emission spectrum, action spectrum for forming (6s6p)3P), and experiments where the number of methane molecules per cluster, which was strictly controlled, was varied systematically. The corresponding results were interpreted on the ground of a model, which transposes both chemical thermodynamics of equilibria and reaction kinetics to CICR experiments. Such an a...
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Cluster isolated chemical reactions: Reactivity of Ba Atoms and small Ba clusters with SF6 and CO2 molecules on large argon clusters
The Journal of Chemical Physics, 1997Co-Authors: Christelle Gée, M.-a. Gaveau, J.-m. Mestdagh, O. Sublemontier, J. P. VisticotAbstract:The cluster isolated chemical reaction technique was used to investigate the reactivity of the Ba/CO2 and Ba/SF6 systems in the environment of Ar≈6000 clusters. The method was extended to document several aspects of the reactivity. Notably, mass spectrometry gives insight into the full reactivity of the system deposited on the clusters. Laser induced fluorescence (LIF) and chemiluminescence are also used as detection tools. Unexpectedly, we found that a single Barium Atom neither reacts with CO2 nor with SF6 at the cluster temperature (32 K). In contrast, the LIF results suggest the formation of a weakly bound covalent Ba…CO2 complex. Finally, Ba2 and larger Barium aggregates react with CO2, and Ba3 and larger aggregates react with SF6. The chemiluminescent products are Ba2O in the first case, and BaF in the second. These observations are rationalized on the ground of the harpoon model.
M.-a. Gaveau - One of the best experts on this subject based on the ideXlab platform.
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multipronged mapping to the dynamics of a Barium Atom deposited on argon clusters
Physical Chemistry Chemical Physics, 2016Co-Authors: S Awali, M. Briant, M.-a. Gaveau, J.-m. Mestdagh, B Soep, O Gobert, R Maksimenka, Lionel PoissonAbstract:The dynamics of an electronically excited Barium Atom deposited at the surface of an Ar≈500 cluster was explored in a multipronged approach which associates information from frequency-resolved nanosecond experiments and information from femtosecond time-resolved experiments. In both types of experiments, the dynamics is monitored by photoelectron and photoion spectroscopy.
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multipronged mapping to the dynamics of a Barium Atom deposited on argon clusters supplementary material
2016Co-Authors: S Awali, M. Briant, M.-a. Gaveau, J.-m. Mestdagh, B Soep, O Gobert, R Maksimenka, Lionel PoissonAbstract:The dynamics of an electronically excited Barium Atom deposited at the surface of an Ar≈500 cluster was explored in a multipronged approach which associates information from frequency-resolved nanosecond experiments and information from femtosecond time-resolved experiments. In both types of experiments, the dynamics is monitored by photoelectron and photoion spectroscopy.
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Observation of a Barium xenon exciplex within a large argon cluster
Journal of Chemical Physics, 2010Co-Authors: M. Briant, M.-a. Gaveau, J.-m. MestdaghAbstract:Spectroscopic measurements provide fluorescence and excitation spectra of a single Barium Atom codeposited with xenon Atoms on argon clusters of average size ≈ 2000. The spectra are studied as a function of the number of xenon Atoms per cluster. The excitation spectrum with ∼ 10 xenon Atoms per cluster is qualitatively similar to that observed when no xenon Atom is present on the cluster. It consists of two bands located on each side of the 6s6p 1P−6s2 1S resonance line of the free Barium. In contrast, the fluorescence spectrum differs qualitatively since a Barium-xenon exciplex is observed, which has no counterpart in xenon free clusters. In particular an emission is observed, which is redshifted by 729 cm−1 with respect to the Ba(6s6p 1P−6s2 1S) resonance line.
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Cluster isolated chemical reaction (CICR) spectroscopy: Ba Atoms and Ba(CH4)n complexes on large neon clusters
The Journal of Chemical Physics, 2000Co-Authors: M. Briant, M.-a. Gaveau, J.-m. Mestdagh, J. P. VisticotAbstract:The cluster isolated chemical reaction (CICR) technique was applied to neon clusters (Ne≈7000) on which Barium Atoms and methane molecules were deposited. Clusters carrying Barium only were studied first. Qualitatively, the present results on neon clusters are in line with our previous results on argon clusters. In particular, surface location of Barium was observed. The central part of the present work concerns neon clusters carrying both one Barium Atom and one to ten methane molecules. Several types of spectroscopy were performed in the region of the resonance transition (6s2)1S→(6s6p)1P of Barium (excitation spectrum of the total fluorescence, emission spectrum, action spectrum for forming (6s6p)3P), and experiments where the number of methane molecules per cluster, which was strictly controlled, was varied systematically. The corresponding results were interpreted on the ground of a model, which transposes both chemical thermodynamics of equilibria and reaction kinetics to CICR experiments. Such an a...
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Cluster isolated chemical reactions: Reactivity of Ba Atoms and small Ba clusters with SF6 and CO2 molecules on large argon clusters
The Journal of Chemical Physics, 1997Co-Authors: Christelle Gée, M.-a. Gaveau, J.-m. Mestdagh, O. Sublemontier, J. P. VisticotAbstract:The cluster isolated chemical reaction technique was used to investigate the reactivity of the Ba/CO2 and Ba/SF6 systems in the environment of Ar≈6000 clusters. The method was extended to document several aspects of the reactivity. Notably, mass spectrometry gives insight into the full reactivity of the system deposited on the clusters. Laser induced fluorescence (LIF) and chemiluminescence are also used as detection tools. Unexpectedly, we found that a single Barium Atom neither reacts with CO2 nor with SF6 at the cluster temperature (32 K). In contrast, the LIF results suggest the formation of a weakly bound covalent Ba…CO2 complex. Finally, Ba2 and larger Barium aggregates react with CO2, and Ba3 and larger aggregates react with SF6. The chemiluminescent products are Ba2O in the first case, and BaF in the second. These observations are rationalized on the ground of the harpoon model.
J. P. Visticot - One of the best experts on this subject based on the ideXlab platform.
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Cluster isolated chemical reaction (CICR) spectroscopy: Ba Atoms and Ba(CH4)n complexes on large neon clusters
The Journal of Chemical Physics, 2000Co-Authors: M. Briant, M.-a. Gaveau, J.-m. Mestdagh, J. P. VisticotAbstract:The cluster isolated chemical reaction (CICR) technique was applied to neon clusters (Ne≈7000) on which Barium Atoms and methane molecules were deposited. Clusters carrying Barium only were studied first. Qualitatively, the present results on neon clusters are in line with our previous results on argon clusters. In particular, surface location of Barium was observed. The central part of the present work concerns neon clusters carrying both one Barium Atom and one to ten methane molecules. Several types of spectroscopy were performed in the region of the resonance transition (6s2)1S→(6s6p)1P of Barium (excitation spectrum of the total fluorescence, emission spectrum, action spectrum for forming (6s6p)3P), and experiments where the number of methane molecules per cluster, which was strictly controlled, was varied systematically. The corresponding results were interpreted on the ground of a model, which transposes both chemical thermodynamics of equilibria and reaction kinetics to CICR experiments. Such an a...
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Cluster isolated chemical reactions: Reactivity of Ba Atoms and small Ba clusters with SF6 and CO2 molecules on large argon clusters
The Journal of Chemical Physics, 1997Co-Authors: Christelle Gée, M.-a. Gaveau, J.-m. Mestdagh, O. Sublemontier, J. P. VisticotAbstract:The cluster isolated chemical reaction technique was used to investigate the reactivity of the Ba/CO2 and Ba/SF6 systems in the environment of Ar≈6000 clusters. The method was extended to document several aspects of the reactivity. Notably, mass spectrometry gives insight into the full reactivity of the system deposited on the clusters. Laser induced fluorescence (LIF) and chemiluminescence are also used as detection tools. Unexpectedly, we found that a single Barium Atom neither reacts with CO2 nor with SF6 at the cluster temperature (32 K). In contrast, the LIF results suggest the formation of a weakly bound covalent Ba…CO2 complex. Finally, Ba2 and larger Barium aggregates react with CO2, and Ba3 and larger aggregates react with SF6. The chemiluminescent products are Ba2O in the first case, and BaF in the second. These observations are rationalized on the ground of the harpoon model.
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Dynamics of the Barium-molecule system within large argon clusters
Zeitschrift für Physik D Atoms Molecules and Clusters, 1994Co-Authors: X. Biquard, M.-a. Gaveau, J.-m. Mestdagh, O. Sublemontier, J. P. Visticot, P. Meynadier, J. BerlandeAbstract:The effects of adding molecules on the LIF at 540 nm of a Barium Atom at the surface of an argon cluster (average size 420) has been investigated. We showed that molecules like ethanol, n -hexane and O_2 from stable complexes with ground state Barium. In the case of molecules like N_2, CH_4 and SF_6, the collisional quenching of solvated Ba(^1 P ) is observed. The large quenching rates obtained are interpreted by a surface mobility of the collisional partners. Moreover, we showed that this collisional quenching leads to the ejection of free Ba(^3 P _1).
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Photodesorption dynamics of Ba Atoms from large Ar clusters
The Journal of Chemical Physics, 1994Co-Authors: B. Schilling, M.-a. Gaveau, J.-m. Mestdagh, O. Sublemontier, J. P. Visticot, X. Biquard, J. BerlandeAbstract:Barium Atoms at the surface of large argon clusters are excited into the 6s6p1P1 state leading either to ejection and subsequent fluorescence of the free Barium Atom or to fluorescence of solvated Barium. Relative probabilities for these two processes as a function of the excitation energy and of the cluster size are presented. By comparison with the binding energy from a molecular dynamics (MD) calculation, we find that the Barium Atom is not excited above the limit for direct dissociation. The nonzero desorption probability is attributed to the gain of surface energy of the argon cluster which is partially transferred to the Barium Atom. Using linearly polarized laser light for the excitation, a positive polarization of the fluorescence of the ejected Barium Atoms is observed, whereas the polarization fluorescence of the solvated Barium is negative. This indicates that the solvated Barium Atoms undergo a relaxation process which rotates the orientation of the excited orbital before the fluorescence. The...
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Experiment versus molecular dynamics simulation: Spectroscopy of Ba-(Ar) n clusters
The Journal of Chemical Physics, 1994Co-Authors: J. P. Visticot, J.-m. Mestdagh, O. Sublemontier, J. Berlande, P. De Pujo, A. Lallement, P. Meynadier, J. CuvellierAbstract:This work presents a quantitative comparison between experiment and molecular dynamics simulations for the excitation spectra of large van der Waals clusters. The emission and excitation spectra of mixed Ba(Ar)n clusters have been obtained for average cluster sizes ranging between 300 and 4000. The simulation is performed by using classical dynamics and pairwise additive potentials for two cases corresponding to the Barium Atom at the surface or inside the argon cluster. A very good agreement with the experiment is found when the Barium Atom is at the surface.
M. Briant - One of the best experts on this subject based on the ideXlab platform.
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multipronged mapping to the dynamics of a Barium Atom deposited on argon clusters
Physical Chemistry Chemical Physics, 2016Co-Authors: S Awali, M. Briant, M.-a. Gaveau, J.-m. Mestdagh, B Soep, O Gobert, R Maksimenka, Lionel PoissonAbstract:The dynamics of an electronically excited Barium Atom deposited at the surface of an Ar≈500 cluster was explored in a multipronged approach which associates information from frequency-resolved nanosecond experiments and information from femtosecond time-resolved experiments. In both types of experiments, the dynamics is monitored by photoelectron and photoion spectroscopy.
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multipronged mapping to the dynamics of a Barium Atom deposited on argon clusters supplementary material
2016Co-Authors: S Awali, M. Briant, M.-a. Gaveau, J.-m. Mestdagh, B Soep, O Gobert, R Maksimenka, Lionel PoissonAbstract:The dynamics of an electronically excited Barium Atom deposited at the surface of an Ar≈500 cluster was explored in a multipronged approach which associates information from frequency-resolved nanosecond experiments and information from femtosecond time-resolved experiments. In both types of experiments, the dynamics is monitored by photoelectron and photoion spectroscopy.
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Observation of a Barium xenon exciplex within a large argon cluster
Journal of Chemical Physics, 2010Co-Authors: M. Briant, M.-a. Gaveau, J.-m. MestdaghAbstract:Spectroscopic measurements provide fluorescence and excitation spectra of a single Barium Atom codeposited with xenon Atoms on argon clusters of average size ≈ 2000. The spectra are studied as a function of the number of xenon Atoms per cluster. The excitation spectrum with ∼ 10 xenon Atoms per cluster is qualitatively similar to that observed when no xenon Atom is present on the cluster. It consists of two bands located on each side of the 6s6p 1P−6s2 1S resonance line of the free Barium. In contrast, the fluorescence spectrum differs qualitatively since a Barium-xenon exciplex is observed, which has no counterpart in xenon free clusters. In particular an emission is observed, which is redshifted by 729 cm−1 with respect to the Ba(6s6p 1P−6s2 1S) resonance line.
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Cluster isolated chemical reaction (CICR) spectroscopy: Ba Atoms and Ba(CH4)n complexes on large neon clusters
The Journal of Chemical Physics, 2000Co-Authors: M. Briant, M.-a. Gaveau, J.-m. Mestdagh, J. P. VisticotAbstract:The cluster isolated chemical reaction (CICR) technique was applied to neon clusters (Ne≈7000) on which Barium Atoms and methane molecules were deposited. Clusters carrying Barium only were studied first. Qualitatively, the present results on neon clusters are in line with our previous results on argon clusters. In particular, surface location of Barium was observed. The central part of the present work concerns neon clusters carrying both one Barium Atom and one to ten methane molecules. Several types of spectroscopy were performed in the region of the resonance transition (6s2)1S→(6s6p)1P of Barium (excitation spectrum of the total fluorescence, emission spectrum, action spectrum for forming (6s6p)3P), and experiments where the number of methane molecules per cluster, which was strictly controlled, was varied systematically. The corresponding results were interpreted on the ground of a model, which transposes both chemical thermodynamics of equilibria and reaction kinetics to CICR experiments. Such an a...
O. Sublemontier - One of the best experts on this subject based on the ideXlab platform.
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Cluster isolated chemical reactions: Reactivity of Ba Atoms and small Ba clusters with SF6 and CO2 molecules on large argon clusters
The Journal of Chemical Physics, 1997Co-Authors: Christelle Gée, M.-a. Gaveau, J.-m. Mestdagh, O. Sublemontier, J. P. VisticotAbstract:The cluster isolated chemical reaction technique was used to investigate the reactivity of the Ba/CO2 and Ba/SF6 systems in the environment of Ar≈6000 clusters. The method was extended to document several aspects of the reactivity. Notably, mass spectrometry gives insight into the full reactivity of the system deposited on the clusters. Laser induced fluorescence (LIF) and chemiluminescence are also used as detection tools. Unexpectedly, we found that a single Barium Atom neither reacts with CO2 nor with SF6 at the cluster temperature (32 K). In contrast, the LIF results suggest the formation of a weakly bound covalent Ba…CO2 complex. Finally, Ba2 and larger Barium aggregates react with CO2, and Ba3 and larger aggregates react with SF6. The chemiluminescent products are Ba2O in the first case, and BaF in the second. These observations are rationalized on the ground of the harpoon model.
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Dynamics of the Barium-molecule system within large argon clusters
Zeitschrift für Physik D Atoms Molecules and Clusters, 1994Co-Authors: X. Biquard, M.-a. Gaveau, J.-m. Mestdagh, O. Sublemontier, J. P. Visticot, P. Meynadier, J. BerlandeAbstract:The effects of adding molecules on the LIF at 540 nm of a Barium Atom at the surface of an argon cluster (average size 420) has been investigated. We showed that molecules like ethanol, n -hexane and O_2 from stable complexes with ground state Barium. In the case of molecules like N_2, CH_4 and SF_6, the collisional quenching of solvated Ba(^1 P ) is observed. The large quenching rates obtained are interpreted by a surface mobility of the collisional partners. Moreover, we showed that this collisional quenching leads to the ejection of free Ba(^3 P _1).
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Photodesorption dynamics of Ba Atoms from large Ar clusters
The Journal of Chemical Physics, 1994Co-Authors: B. Schilling, M.-a. Gaveau, J.-m. Mestdagh, O. Sublemontier, J. P. Visticot, X. Biquard, J. BerlandeAbstract:Barium Atoms at the surface of large argon clusters are excited into the 6s6p1P1 state leading either to ejection and subsequent fluorescence of the free Barium Atom or to fluorescence of solvated Barium. Relative probabilities for these two processes as a function of the excitation energy and of the cluster size are presented. By comparison with the binding energy from a molecular dynamics (MD) calculation, we find that the Barium Atom is not excited above the limit for direct dissociation. The nonzero desorption probability is attributed to the gain of surface energy of the argon cluster which is partially transferred to the Barium Atom. Using linearly polarized laser light for the excitation, a positive polarization of the fluorescence of the ejected Barium Atoms is observed, whereas the polarization fluorescence of the solvated Barium is negative. This indicates that the solvated Barium Atoms undergo a relaxation process which rotates the orientation of the excited orbital before the fluorescence. The...
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Experiment versus molecular dynamics simulation: Spectroscopy of Ba-(Ar) n clusters
The Journal of Chemical Physics, 1994Co-Authors: J. P. Visticot, J.-m. Mestdagh, O. Sublemontier, J. Berlande, P. De Pujo, A. Lallement, P. Meynadier, J. CuvellierAbstract:This work presents a quantitative comparison between experiment and molecular dynamics simulations for the excitation spectra of large van der Waals clusters. The emission and excitation spectra of mixed Ba(Ar)n clusters have been obtained for average cluster sizes ranging between 300 and 4000. The simulation is performed by using classical dynamics and pairwise additive potentials for two cases corresponding to the Barium Atom at the surface or inside the argon cluster. A very good agreement with the experiment is found when the Barium Atom is at the surface.
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Spectroscopy of Ba—(Ar)n clusters
Chemical Physics Letters, 1992Co-Authors: J. P. Visticot, J.-m. Mestdagh, J. Berlande, P. De Pujo, A. Lallement, P. Meynadier, J. Cuvellier, O. SublemontierAbstract:Abstract The absorption and emission of Barium Atoms trapped onto large argon clusters (about 2000 Atoms) have been observed. The emission consists in a single peak to the red of the Barium resonance line and the absorption of two bands, one on each side of the resonance line. The existence of two absorptions seems characteristic of a configuration where the Barium Atom remains at the surface of the argon cluster.