3.2.2. Isothermal compressibility
Isothermal compressibility was evaluated using the relation Fig. 6 shows isothermal compressibility evaluated with Eq. (3) as a function of pressure at T ¼ 20 C. Due to the presence of liquid-tosolid phase transition the curve in Fig. 6 is discontinuous. Isothermal compressibility of the high-pressure phase is lower than that in the case of the low-pressure phase. This shows that the high-pressure phase exhibit properties similar to a solid-like medium. The spread of points in Fig. 6 results from the numerical evaluation of the derivative in Eq. (3). The solid line is an approximation
of the computed points of isothermal compressibility. Numerical calculations of the derivative are always accompanied by errors. This leads to the spreading of points in Fig. 6.