Entity

Time filter

Source Type


Rosato J.,CNRS Physics Laboratory Ionic and Molecular Interactions ( PIIM )
Physical Review Letters | Year: 2011

A kinetic photon transport model that accounts for spatial coherence is applied to line radiation in optically thick plasmas. It is shown that the photon emission and absorption processes are delocalized in space, which alters the global plasma opacity to spectral lines. Based on this analysis, we demonstrate that spectral profiles and escape factors can be much larger than expected from usual formulas. © 2011 American Physical Society. Source


Danger G.,CNRS Physics Laboratory Ionic and Molecular Interactions ( PIIM ) | Plasson R.,Harvard University | Pascal R.,Montpellier University
Chemical Society Reviews | Year: 2012

α-Amino acids are easily accessible through abiotic processes and were likely present before the emergence of life. However, the role they could have played in the process remains uncertain. Chemical pathways that could have brought about features of self-organization in a peptide world are considered in this review and discussed in relation with their possible contribution to the origin of life. An overall scheme is proposed with an emphasis on possibilities that may have led to dynamically stable far from equilibrium states. This analysis defines new lines of investigation towards a better understanding of the contribution of the systems chemistry of amino acids and peptides to the emergence of life. © 2012 The Royal Society of Chemistry. Source


Allouche A.,CNRS Physics Laboratory Ionic and Molecular Interactions ( PIIM )
Journal of Physical Chemistry C | Year: 2011

This article reports on calculations carried out using the first-principles density functional theory (DFT) on the oxidation process of the beryllium surface and the consequences on hydrogen atom retention. The oxygen molecule adsorption/dissociation reaction is investigated above the special symmetry points (above a surface atom on top and in bridge position, and in the hollow sites of the hexagonal lattice) of the beryllium basal surface. The corresponding energy profiles are built for both the triplet ground state and the singlet first excited state. The structure of the oxidized layer is proposed. A comparison is then given between hydrogen adsorption on partly oxidized beryllium and hydrogen adsorption on beryllium oxide. © 2011 American Chemical Society. Source


Allouche A.,CNRS Physics Laboratory Ionic and Molecular Interactions ( PIIM )
Surface Science | Year: 2013

Density functional calculations are here carried out to study the carbon monoxide molecule adsorption on pristine, hydrogenated and hydroxylated beryllium Be (0001) surfaces. The adsorption energies and structures, the activation barriers to molecular adsorption and dissociation are calculated. These reactions are described in terms of potential energy surfaces and electronic density of states. The quantum results are discussed along two directions: the beryllium surface reactivity in the domain of nuclear fusion devices and the possible usage of beryllium as a catalyst of Fischer-Tropsch-type synthesis. © 2012 Elsevier B.V. All rights reserved. Source


Rosato J.,CNRS Physics Laboratory Ionic and Molecular Interactions ( PIIM )
Transport Theory and Statistical Physics | Year: 2012

The quantum phase space formalism proposed by Wigner is applied to radiation transport problems. It is shown that a generalization of the radiative transfer equation, which accounts for coherence effects, can be obtained within the second quantization formalism. A simplification in the case of stationary medium and slab geometry is considered and applied to low- and high-density plasmas. The obtained results indicate that spectra can be misinterpreted if the light's spatial coherence is neglected. © 2012 Copyright Taylor and Francis Group, LLC. Source

Discover hidden collaborations