INQUISUR   21779
INSTITUTO DE QUIMICA DEL SUR
Unidad Ejecutora - UE
artículos
Título:
Evidence of a two-state picture for supercooled water and its connections with glassy dynamics
Autor/es:
G.A. APPIGNANESI; J.A. RODRÍGUEZ FRIS; F. SCIORTINO
Revista:
European Physical Journal E
Editorial:
EDP Sciences, Società Italiana di Fisica and Springer-Verlag
Referencias:
Año: 2009 vol. 29 p. 305 - 310
ISSN:
1292-8941
Resumen:
The picture of liquid water as consisting of a mixture of molecules of two different structural states (structured, low-density molecules and unstructured, high-density ones) represents a belief that has been around for long time awaiting for a conclusive validation. While in the last years some indicators have indeed provided certain evidence for the existence of structurally different “species”, a more definite bimodality in the distribution function of a sound structural quantity would be desired. In this context, our present work combines the use of a structural parameter with a minimization technique to yield neat bimodal distributions in a temperature range within the supercooled liquid regime, thus clearly revealing the presence of two populations of differently structured water molecules. Furthermore, we elucidate the role of the inter-conversion between the identified two kinds of states for the dynamics of structural relaxation, thus linking structural information to dynamics, a long-standing issue in glassy physics.