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1. Structural and Microscopic Relaxation Processes in Liquid Hydrogen Fluoride

Author

Angelini, R., Giura, P., Monaco, G., Ruocco, G., Sette, F., and Verbeni, R.

Subjects
Condensed Matter - Soft Condensed Matter, Condensed Matter - Disordered Systems and Neural Networks
Abstract

The high frequency collective dynamics of liquid hydrogen fluoride is studied by inelastic x-ray scattering on the coexistence curve at T = 239 K. The comparison with existing molecular dynamics simulations shows the existence of two active relaxation processes with characteristic time scales in the subpicosecond range. The observed scenario is very similar to that found in liquid water. This suggests that hydrogen bonded liquids behave similarly to other very different systems as simple and glass forming liquids, thus indicating that these two relaxation processes are universal features of the liquid state., Comment: 6 pages, 5 figures

Published
2023
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2. Silicon crystals for steering of high-intensity particle beams at ultra-high energy accelerators

Author

Mazzolari, A., Romagnoni, M., Bagli, E., Bandiera, L., Baricordi, S., Camattari, R., Casotti, D., Tamisari, M., Sytov, A., Guidi, V., Cavoto, G., Carturan, S., De Salvador, D., Balbo, A., Cruciani, G., Trans, Thu Nhi, Verbeni, R., Pastrone, N., Lanzoni, L., Rossall, A., Berg, J. A. van den, Jenkins, R., and Dumas, P.

Subjects
Physics - Accelerator Physics, High Energy Physics - Experiment
Abstract

Experimental results and simulation models show that crystals might play a relevant role for the development of new generations of high-energy and high-intensity particle accelerators and might disclose innovative possibilities at existing ones. In this paper we describe the most advanced manufacturing techniques of crystals suitable for operations at ultra-high energy and ultra-high intensity particle accelerators, reporting as an example of potential applications the collimation of the particle beams circulating in the Large Hadron Collider at CERN, which will be upgraded through the addition of bent crystals in the frame of the High Luminosity Large Hadron Collider project.

Published
2020
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4. (p,T,H) phase diagram of Heavy Fermion systems : Some systematics and some surprises from ytterbium

Author

Braithwaite, D., Fernandez-Pañella, A., Colombier, E., Salce, B., Knebel, G., Lapertot, G., Balédent, V., Rueff, J. -P., Paolasini, L., Verbeni, R., and Flouquet, J.

Subjects
Condensed Matter - Strongly Correlated Electrons
Abstract

Pressure is the cleanest way to tune heavy fermion systems to a quantum phase transition in order to study the rich physics and competing phases, and the comparison between ytterbium and cerium systems is particularly fruitful. We briefly review the mechanisms in play and show some examples of expected and unexpected behaviour. We emphasize the importance of the valence changes under pressure and show how modern synchrotron techniques can accurately determine this, including at low temperature., Comment: To appear in proceedings of International Conference on Superconductivity and Magnetism ICSM 2012 (Istanbul)

Published
2012

5. High frequency longitudinal and transverse dynamics in water

Author

Pontecorvo, E., Krisch, M., Cunsolo, A., Monaco, G., Mermet, A., Verbeni, R., Sette, F., and Ruocco, G.

Subjects
Condensed Matter - Disordered Systems and Neural Networks
Abstract

High-resolution, inelastic x-ray scattering measurements of the dynamic structure factor S(Q,\omega) of liquid water have been performed for wave vectors Q between 4 and 30 nm^-1 in distinctly different thermodynamic conditions (T= 263 - 420 K ; at, or close to, ambient pressure and at P = 2 kbar). In agreement with previous inelastic x-ray and neutron studies, the presence of two inelastic contributions (one dispersing with Q and the other almost non-dispersive) is confirmed. The study of their temperature- and Q-dependence provides strong support for a dynamics of liquid water controlled by the structural relaxation process. A viscoelastic analysis of the Q-dispersing mode, associated with the longitudinal dynamics, reveals that the sound velocity undergoes the complete transition from the adiabatic sound velocity (c_0) (viscous limit) to the infinite frequency sound velocity (c_\infinity) (elastic limit). On decreasing Q, as the transition regime is approached from the elastic side, we observe a decrease of the intensity of the second, weakly dispersing feature, which completely disappears when the viscous regime is reached. These findings unambiguously identify the second excitation to be a signature of the transverse dynamics with a longitudinal symmetry component, which becomes visible in the S(Q,\omega) as soon as the purely viscous regime is left., Comment: 28 pages, 12 figures

Published
2005
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6. Phonon-like and single particle dynamics in liquid lithium

Author

Scopigno, T., Balucani, U., Cunsolo, A., Masciovecchio, C., Ruocco, G., Sette, F., and Verbeni, R.

Subjects
Condensed Matter - Disordered Systems and Neural Networks
Abstract

The dynamic structure factor, S(Q,E), of liquid lithium (T=475 K) has been determined by inelastic x-ray scattering (IXS) in the momentum transfer region (Q = 1.4-110 nm-1). These data allow to observe how, in a simple liquid, a phonon-like collective mode evolves towards the single particle dynamics. As a function of Q, one finds: i) at low Q's, a sound mode with a positive dispersion of the sound velocity, ii) at intermediate Q's, excitations whose energy oscillates similarly to phonons in the crystal Brillouin zones, and iii) at high Q's, the S(Q,E) approaches a Gaussian shape, indicating that the single particle dynamics has been reached., Comment: 3 pages and 5 figures

Published
1999
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7. Acoustic Nature of the Boson Peak in Vitreous Silica

Author

Masciovecchio, C., Mazzacurati, V., Monaco, G., Ruocco, G., Scopigno, T., Sette, F., Benassi, P., Cunsolo, A., Fontana, A., Krisch, M., Mermet, A., Montagna, M., Rossi, F., Sampoli, M., Signorelli, G., and Verbeni, R.

Subjects
Condensed Matter - Disordered Systems and Neural Networks
Abstract

New temperature dependent inelastic x-ray (IXS) and Raman (RS) scattering data are compared to each other and with existing inelastic neutron scattering data in vitreous silica (v-SiO_2), in the 300 - 1775 K region. The IXS data show collective propagating excitations up to Q=3.5 nm^-1. The temperature behaviour of the excitations at Q=1.6 nm^-1 matches that of the boson peak found in INS and RS. This supports the acoustic origin of the excess of vibrational states giving rise to the boson peak in this glass., Comment: 10 pages and 4 figures

Published
1999

12. Silicon crystals for steering high-intensity particle beams at ultrahigh-energy accelerators

Author

Mazzolari, A., primary, Romagnoni, M., additional, Bagli, E., additional, Bandiera, L., additional, Baricordi, S., additional, Camattari, R., additional, Casotti, D., additional, Tamisari, M., additional, Sytov, A., additional, Guidi, V., additional, Cavoto, G., additional, Carturan, S. M., additional, De Salvador, D., additional, Balbo, A., additional, Cruciani, G., additional, Tran Caliste, Thu Nhi, additional, Verbeni, R., additional, Pastrone, N., additional, Lanzoni, L., additional, Rossall, A., additional, van den Berg, J. A., additional, Jenkins, R., additional, and Dumas, P., additional

Published
2021
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18. A high-energy-resolution resonant inelastic X-ray scattering spectrometer at ID20 of the European Synchrotron Radiation Facility

Author

Moretti Sala, M., primary, Martel, K., additional, Henriquet, C., additional, Al Zein, A., additional, Simonelli, L., additional, Sahle, Ch. J., additional, Gonzalez, H., additional, Lagier, M.-C., additional, Ponchut, C., additional, Huotari, S., additional, Verbeni, R., additional, Krisch, M., additional, and Monaco, G., additional

Published
2018
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19. The single particle dynamics of iodine in the Sachs-Teller regime: An inelastic x-ray scattering study.

Author

Izzo, M. G., Bencivenga, F., Cunsolo, A., Di Fonzo, S., Verbeni, R., and De Lorenzo, R. Gimenez

Subjects
PARTICLE dynamics, IODINE, X-ray scattering, MOLECULAR spectra, CHEMISTRY experiments, CHEMICAL kinetics
Abstract

The high frequency dynamics of liquid iodine has been investigated by deep inelastic x-ray scattering at exchanged wave-vectors (q) ranging from 2.5 to 15 Å-1. The experimental data have been analyzed in the frame of the Sachs-Teller theory of the molecular spectrum while accounting for final state corrections to the lineshape. The performed data analysis carries insights on physical quantities as relevant as the mean rototranslational kinetic energy and the mean square Laplacian of the intermolecular potential. In both cases the measured values are consistent with corresponding theoretical expectations. [ABSTRACT FROM AUTHOR]

Published
2010
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20. Onset of the α-relaxation in the glass-forming solution LiCl–6H2O revealed by Brillouin scattering techniques.

Author

Santucci, S. C., Comez, L., Scarponi, F., Monaco, G., Verbeni, R., Legrand, J.-F., Masciovecchio, C., Gessini, A., and Fioretto, D.

Subjects
WATER of crystallization, LIGHT beating spectroscopy, BRILLOUIN scattering, PHYSIOLOGICAL effects of ultraviolet radiation, RELAXATION (Nuclear physics)
Abstract

We measured the dynamic structure factor of the liquid and glassy phases of the LiCl–6H2O solution by means of inelastic scattering of radiation in the visible, UV, and x-ray range, between 1 GHz and 10 THz, and by means of photon-correlation spectroscopy, between 0.01 Hz and 20 kHz. The measurements were performed in the temperature range between 353 and 80 K. Our data show that a single-relaxation process exists at high temperature, which has features similar to those of the single relaxation of pure water. Upon cooling the system below ∼220 K, this single mode starts to differentiate two processes, a structural (α-) and a secondary (β-) relaxation. As the temperature is decreased, the β-relaxation is the vanishing continuation of the single, high-temperature process, while the onset of the α-relaxation occurs at the expense of the β-process. [ABSTRACT FROM AUTHOR]

Published
2009
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21. Signatures of quantum behavior in the microscopic dynamics of liquid hydrogen and deuterium.

Author

Cunsolo, A., Colognesi, D., Sampoli, M., Senesi, R., and Verbeni, R.

Subjects
LIQUEFIED gases, LIQUID hydrogen, DEUTERIUM, X-ray scattering, MONTE Carlo method, QUANTUM theory
Abstract

We discuss the microscopic dynamics and structure of liquid hydrogen and deuterium, as probed by inelastic x-ray scattering measurements. Samples are kept in corresponding thermodynamic conditions, at which classical systems are expected to exhibit the same dynamic and static responses. On the contrary, we observe clear differences revealing the onset of quantum deviations, both in the broadening of inelastic excitations and in the position of the first sharp diffraction peak. These features are discussed, compared to path-integral Monte Carlo simulations, and finally associated with the different de Broglie wavelengths of the two isotopes. [ABSTRACT FROM AUTHOR]

Published
2005
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22. A large-solid-angle X-ray Raman scattering spectrometer at ID20 of the European Synchrotron Radiation Facility

Author

Huotari, S., primary, Sahle, Ch. J., additional, Henriquet, Ch., additional, Al-Zein, A., additional, Martel, K., additional, Simonelli, L., additional, Verbeni, R., additional, Gonzalez, H., additional, Lagier, M.-C., additional, Ponchut, C., additional, Moretti Sala, M., additional, Krisch, M., additional, and Monaco, G., additional

Published
2017
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23. Experimental setup for high energy photoemission using synchrotron radiation RID F-8940-2010 RID G-7348-2011

Author

Torelli P, Sacchi M, Cautero G, Cautero M, Krastanov B, Lacovig P, Pittana P, Sergo R, Tommasini R, Fondacaro A, Offi F, Paolicelli G, Grioni M, Verbeni R, Monaco G, Panaccione G., STEFANI, Giovanni, Torelli, P, Sacchi, M, Cautero, G, Cautero, M, Krastanov, B, Lacovig, P, Pittana, P, Sergo, R, Tommasini, R, Fondacaro, A, Offi, F, Paolicelli, G, Stefani, Giovanni, Grioni, M, Verbeni, R, Monaco, G, and Panaccione, G.

Abstract

The instrument VOLPE (volume photoemission from solids) is an experimental setup dedicated to high energy photoemission (PE) experiments. The instrument is equipped with an electrostatic hemispherical spectrometer especially designed to analyze high energy electrons (up to 10 keV) with high resolving power. In order to attain an energy resolution of a few tens of millielectron volts, we designed and constructed a dedicated input lens system, high stability power supplies, and a low dark-count detector and readout electronics. The system has been tested and is now operational on the ID16 beamline at European Synchrotron Radiation Facility, where an optical layout has been developed to perform high energy, high resolution PE experiments. First results show an overall energy resolution (electron + photon) of 71+/-7 meV at 5934 eV. The effective attenuation length of the photoelectrons is estimated to be 5+/-0.5 nm at a kinetic energy of 5 keV. (C) 2005 American Institute of Physics.

Published
2005

24. Valence instability of YbCu2Si2 through its magnetic quantum critical point

Author

Fernandez-Panella, A., Balédent, V., Braithwaite, D., Paolasini, L., Verbeni, R., Lapertot, G., Rueff, J.-P., Service de Physique Statistique, Magnétisme et Supraconductivité (SPSMS - UMR 9001), Institut Nanosciences et Cryogénie (INAC), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Instrumentation, Material and Correlated Electrons Physics (IMAPEC), PHotonique, ELectronique et Ingénierie QuantiqueS (PHELIQS), Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Laboratoire de Physique des Solides (LPS), Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS), European Synchrotron Radiation Facility (ESRF), Synchrotron SOLEIL (SSOLEIL), Centre National de la Recherche Scientifique (CNRS), Laboratoire de Chimie Physique - Matière et Rayonnement (LCPMR), and Institut de Chimie du CNRS (INC)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[PHYS]Physics [physics], [PHYS.COND]Physics [physics]/Condensed Matter [cond-mat], [PHYS.COND.CM-SCE]Physics [physics]/Condensed Matter [cond-mat]/Strongly Correlated Electrons [cond-mat.str-el], ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2012

25. Valence instability of YbCu 2 Si 2 through its magnetic quantum critical point

Author

Fernandez-Panella, A., Balédent, V., Braithwaite, D., Paolasini, L., Verbeni, R., Lapertot, G., Rueff, J.-P., Service de Physique Statistique, Magnétisme et Supraconductivité (SPSMS - UMR 9001), Institut Nanosciences et Cryogénie (INAC), Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Instrumentation, Material and Correlated Electrons Physics (IMAPEC), PHotonique, ELectronique et Ingénierie QuantiqueS (PHELIQS), Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Laboratoire de Physique des Solides (LPS), Centre National de la Recherche Scientifique (CNRS)-Université Paris-Sud - Paris 11 (UP11), European Synchrotron Radiation Facility (ESRF), Synchrotron SOLEIL (SSOLEIL), Centre National de la Recherche Scientifique (CNRS), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])

Subjects
[PHYS]Physics [physics], [PHYS.COND]Physics [physics]/Condensed Matter [cond-mat], [PHYS.COND.CM-SCE]Physics [physics]/Condensed Matter [cond-mat]/Strongly Correlated Electrons [cond-mat.str-el], ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2012

34. Magnetic and structural $\alpha - \epsilon$ phase transition in Fe monitored by x-ray emission spectroscopy

Author

Rueff, J. P., Krisch, M., Cai, Y. Q., Kaprolat, A., Hanfland, M., Lorenzen, M., Masciovecchio, C., Verbeni, R., and Sette, F.

Subjects
ddc:530
Abstract

Physical review / B 60(21), 14510 - 14512 (1999). doi:10.1103/PhysRevB.60.14510, The iron structural and magnetic transition between the magnetic (bcc-α) and the nonmagnetic (hcp-ε)phases has been studied monitoring the pressure dependence of the Fe-Kβ fluorescence line excited with monochromatic synchrotron radiation. The relative intensity of the two multiplets shows an S-shaped pressure curve with flex point at the known transition pressure of 130 kbar. The S width of ≈30kbar also coincides with the one determined in structural determinations, and in magnetism studies using Mössbauer techniques. This shows how the x-ray emission method can be used to probe the local magnetic properties of atoms under extreme thermodynamic conditions., Published by Inst., Woodbury, NY

Published
1999
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