Guo, YY , Chinese Acad Sci, Key Lab Frontiers Theoret Phys, Inst Theoret Phys, POB 2735, Beijing 100190, Peoples R China
部门归属:
[Guo, YY; Chen, XS] Chinese Acad Sci, Key Lab Frontiers Theoret Phys, Inst Theoret Phys, Beijing 100190, Peoples R China
英文摘要:
By considering the fluctuation of grand potential Omega around equilibrium with respect to small one-particle density fluctuations delta rho(alpha)((gamma) over right arrow), the phase instability of restricted primitive model (RPM) of ionic systems is investigated. We use the integral equation theory to calculate the direct correlation functions in the reference hypernetted chain approximation and obtain the spinodal line of RPM. Our analysis explicitly indicates that the gas-fluid phase instability is induced by k = 0 fluctuation mode, while the fluid-solid phase instability is related to k not equal 0 fluctuation modes. The spinodal line is qualitatively consistent with the result or computer simulations by others.