TANAKA LAB. Physics of Soft Condensed Matter The University of Tokyo Graduate School of Engineering Department of Applied Physics The University of Tokyo Institute of Industrial Science Department of Fundamental Engineering
Entrance > Research > Liquid, Glass, Gel > Two-Order Parameter Model > Simple View of Waterlike Anomalies
Polymer, Liquid Crystal, Colloid, Membrane, ProteinLiquid, Glass, GelLight and Soft Matter
Liquid-Liquid Transition in the Molecular LiquidCritical-Like Phenomena Associated with Liquid-Liquid TransitionLiquid-Liquid Transition under Spatial ConfinementSimple View of Waterlike AnomaliesTwo-Order-Parameter Description of Critical Phenomena and Phase Separation of Supercooled LiquidsTwo-Order-Parameter Description of Glass Transition Covering Its Strong to Fragile LimitFrustration on the Way to Crystallization in GlassGlass Transition in a Polydispersed Colloidal SystemGlass Transition and Jamming in a Driven Granular SystemAging and Shear Rejuvenation of a Colloidal GlassKinetics of Crystallization under a Glass Transition TemperatureViolation of the Incompressibility of Liquid by Simple Shear Flow

Simple View of Waterlike Anomalies

Simple View of Waterlike Anomalies We propose that the shape of the equilibrium T-P phase diagram of a liquid is strongly correlated with the thermodynamic anomalies and the ease of vitrification. The T-P phase diagram of water is characterized by its shape. By using this specific shape of the phase diagram as a fingerprint, we classify five elements Si, Ge, Sb, Bi, and Ga into water-type atomic liquids. Similarly, some group III-V (e.g., InSb, GaAS, and GaP) and II-VI compounds (e.g., HgTe, CdTe, and CdSe) are also classified into water-type liquids. We demonstrate that the phase behaviors and the thermodynamic and kinetic behaviors of these liquids can be described by the two-order-parameter model that deals with not only density ordering but also bond ordering. In these liquids, the former represents the metallic-bond nature favoring the isotropic symmetry and tries to increase the density upon ordering, while the latter represents the covalent-bond nature favoring the tetrahedral symmetry and tries to decrease it upon ordering. Thus, they are intrinsically competing. This model well explains the shape of the phase diagram, the temperature dependence of the structure factor, and the thermodynamic anomalies of density and heat capacity of liquid Si in a coherent manner. It also predicts that these water-type liquids will be very poor glass formers at ambient pressure, but their glass-forming ability should increase with increasing pressure. This increase in the glass-forming ability is not only due to the thermodynamic reasons, but also due to the kinetic ones.