IS A 2-STATE MODEL APPROACH APPLICABLE TO LIQUID WATER

It has been suggested that a two-state model theory is applicable to many physical properties of liquid water. On the basis of various proposed two-state water models, we found the calculated adiabatic relaxational compressibility of liquid water to exceed the measured value. By use of the empirical coefficient obtained by a two-state model approach to the isobar expansivity, it is found that the calculated value of the adiabatic compressibility at infinite frequency has a negative value for the various two-state models proposed. In the calculation of heat capacity (CV,∞) at constant volume and infinite frequency, the result also contradicts physical observations such that CV,∞<0. Therefore, it seems that these model theories are inapplicable to liquid water. © 1980 American Institute of Physics.