Molecular dynamics (MD) results for the dynamic structure of a He0.77Ne0.23 gas mixture at two densities (15.8 and 36.1 nm-3) show a clear crossover from hydrodynamic modes to distinct excitations for the two species. The higher density dispension curve neatly shows high- and low-frequency branches setting on with a rather localized transition. The lower density results agree very well with existing neutron scattering data and, in particular, display hydrodynamic behavior up to k≈2 nm-1, in contrast with the conclusions of previous simulation studies. A smooth transition to fast sound is shown to take place for 2<k/nm-1<5, where the present MD data fill the existing gap in the experimental results
Dynamic Structure of He-Ne Mixtures by Molecular Dynamics Simulation: From Hydrodynamic to Fast and Slow Sound Modes / M. Sampoli; U. Bafile; E. Guarini; F. Barocchi. - In: PHYSICAL REVIEW LETTERS. - ISSN 0031-9007. - STAMPA. - 88:(2002), pp. 085502-1-085502-4. [10.1103/PhysRevLett.88.085502]
Dynamic Structure of He-Ne Mixtures by Molecular Dynamics Simulation: From Hydrodynamic to Fast and Slow Sound Modes
SAMPOLI, MARCO;GUARINI GRISALDI TAJA O DEL TAJA, ELEONORA;BAROCCHI, FABRIZIO
2002
Abstract
Molecular dynamics (MD) results for the dynamic structure of a He0.77Ne0.23 gas mixture at two densities (15.8 and 36.1 nm-3) show a clear crossover from hydrodynamic modes to distinct excitations for the two species. The higher density dispension curve neatly shows high- and low-frequency branches setting on with a rather localized transition. The lower density results agree very well with existing neutron scattering data and, in particular, display hydrodynamic behavior up to k≈2 nm-1, in contrast with the conclusions of previous simulation studies. A smooth transition to fast sound is shown to take place for 2I documenti in FLORE sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.