A singular thermodynamically consistent temperature at the origin of the anomalous behavior of liquid water

Date
2012-12-18
Authors
Mallamace, Francesco
Corsaro, Carmelo
Stanley, H. Eugene
Version
Published version
OA Version
Citation
Francesco Mallamace, Carmelo Corsaro, H. Eugene Stanley. 2012. "A singular thermodynamically consistent temperature at the origin of the anomalous behavior of liquid water." SCIENTIFIC REPORTS, Volume 2. https://doi.org/10.1038/srep00993
Abstract
The density maximum of water dominates the thermodynamics of the system under ambient conditions, is strongly P-dependent and disappears at a crossover pressure Pcross ~ 1.8 kbar. We study this variable across a wide area of the T–P phase diagram. We consider old and new data of both the isothermal compressibility KT(T, P) and the coefficient of thermal expansion αP(T, P). We observe that KT(T) shows a minimum at T* ~ 315±5 K for all the studied pressures. We find the behavior of αP to also be surprising: all the αP(T) curves measured at different P cross at T*. The experimental data show a “singular and universal expansivity point” at T* ~ 315 K and αP(T*) ≃ 0.44 10−3 K−1. Unlike other water singularities, we find this temperature to be thermodynamically consistent in the relationship connecting the two response functions.
Description
License
This work is licensed under a Creative Commons Attribution 3.0 Unported License.