Role of the single-particle dynamics in the transverse current autocorrelation function of a liquid metal
- Author(s)
- Eleonora Guarini, Ubaldo Bafile, Daniele Colognesi, Alessandro Cunsolo, Alessio De Francesco, Ferdinando Formisano, Wouter Montfrooij, Martin Neumann, Fabrizio Barocchi
- Abstract
A recent simulation study of the transverse current autocorrelation of the Lennard-Jones fluid [Guarini et al., Phys. Rev. E 107, 014139 (2023)] revealed that this function can be perfectly described within the exponential expansion theory [Barocchi et al., Phys. Rev. E 85, 022102 (2012)]. However, above a certain wavevector Q, not only transverse collective excitations were found to propagate in the fluid, but a second oscillatory component of unclear origin (therefore called X) must be considered to fully account for the time dependence of the correlation function. Here, we present an extended investigation of the transverse current autocorrelation of liquid Au as obtained by ab initio molecular dynamics in the very wide range of wavevectors 5.7 ≤ Q ≤ 32.8 nm
−1 in order to also follow the behavior of the X component, if present, at large Q values. A joint analysis of the transverse current spectrum and its self-portion indicates that the second oscillatory component arises from the longitudinal dynamics, as suggested by its close resemblance with the previously determined component accounting for the longitudinal part of the density of states. We conclude that such a mode, albeit featuring a merely transverse property, fingerprints the effect of longitudinal collective excitations on single-particle dynamics, rather than arising from a possible coupling between transverse and longitudinal acoustic waves.
- Organisation(s)
- Computational and Soft Matter Physics
- External organisation(s)
- University of Florence, Institute of Genetics and Biophysics "Adriano Buzzati-Traverso", CNR, University of Wisconsin, Madison, Institut Laue-Langevin (ILL), University of Missouri-Columbia
- Journal
- Journal of Chemical Physics
- Volume
- 158
- No. of pages
- 9
- ISSN
- 0021-9606
- DOI
- https://doi.org/10.1063/5.0152090
- Publication date
- 06-2023
- Peer reviewed
- Yes
- Austrian Fields of Science 2012
- 103015 Condensed matter, 103043 Computational physics, 103029 Statistical physics
- ASJC Scopus subject areas
- General Physics and Astronomy, Physical and Theoretical Chemistry
- Portal url
- https://ucrisportal.univie.ac.at/en/publications/b39e9ab2-2cee-44de-99ab-2bb9a605786d