Equations of State of Atoms for the Thomas-Fermi Theory (Applications for Atoms under a High Pressure)

The most simple model of atoms is a spherical atom in which the charge due to electrons is uni-formly distributed. In the second model, the potential in an atom is expressed, instead of a uniform distribution, as a function of distance from the central nucleus concerned. In this case, by introduc-ing a non-dimensional statistical potential, quantitative stimates of atomic behavior can be approx-imately made. This is called the Thomas-Fermi (TF) method. This method is much simpler than the self-consistent field method, but in some cases, at least for the ground state of atoms, the TF method is useful without critical loss of accuracy. The principle of the TF method is reviewed as well as applications of the method for atoms compressed under a high pressure. I