Quantum Effects on Liquid Dynamics as Evidenced by the Presence of Well-Defined Collective Excitations in Liquid <i>para</i>-Hydrogen

F. J. Bermejo; K. Kinugawa; C. Cabrillo; S. M. Bennington; B. Fåk; M. T. Fernández-Díaz; P. Verkerk; J. Dawidowski; R. Fernández-Perea

doi:10.1103/PhysRevLett.84.5359

Quantum Effects on Liquid Dynamics as Evidenced by the Presence of Well-Defined Collective Excitations in Liquid para-Hydrogen

F. J. Bermejo, K. Kinugawa, C. Cabrillo, S. M. Bennington, B. Fåk, M. T. Fernández-Díaz, P. Verkerk, J. Dawidowski, and R. Fernández-Perea

Phys. Rev. Lett. 84, 5359 – Published 5 June 2000

Abstract

The origin of the well-defined collective excitations found in liquid $para - H_{2}$ by recent experiments is investigated. The persistence of their relatively long lifetimes down to microscopic scales is well accounted for by calculations carried out by means of path-integral-centroid molecular dynamics. In contrast only overdamped excitations are found in calculations carried within the classical limit. The results provide fully quantitative evidence of quantum effects on the dynamics of a simple liquid.

Received 6 December 1999

DOI:https://doi.org/10.1103/PhysRevLett.84.5359

Authors & Affiliations

F. J. Bermejo¹, K. Kinugawa², C. Cabrillo¹, S. M. Bennington³, B. Fåk⁴, M. T. Fernández-Díaz⁵, P. Verkerk⁶, J. Dawidowski¹, and R. Fernández-Perea⁷

¹Consejo Superior de Investigaciones Científicas, Serrano 121-123, E-28006 Madrid, Spain
²Department of Chemistry, Nara Women's University, Nara 630-8506, Japan
³Rutherford Appleton Laboratory, Chilton, Didcot, Oxon OX11 OQX, United Kingdom
⁴Département de Recherche Fondamentale sur la Matière Condensée, SPSMS, CEA, F-38054 Grenoble, France
⁵Institut Laue Langevin, BP 156, F-38042 Grenoble Cedex 9, France
⁶Interfaculty Reactor Institute, Mekelweg 15, 2629 JB Delft, The Netherlands
⁷Argonne National Laboratory, Argonne, Illinois 60439