S. Wahyuni, W.S.B. Dwandaru, M.F. Rosyid
Estimation of the minimizer of the Thomas-Fermi-Dirac-von Weizsacker functional of NaCl crystal lattice is calculated by making use of a direct method we have developed recently. The method is referred to as direct method for the reason that in the course of the calculation of the estimation, we do not derive the Euler-Lagrange equation at all. By using the graph of the umbrella functions, the estimation of the minimizer function is represented. The minimizer is bounded from above by the umbrella functions.
Kelompok Penelitian Kosmologi, Astrofisika Dan Fisika Matematik (KAM), Jurusan Fisika FMIPA, Universitas Gadjah Mada, Yogyakarta, Indonesia; Jurusan Fisika FMIPA Universitas Negeri Semarang, Indonesia; Jurusan Pendidikan Fisika FMIPA, Universitas Negeri, Yogyakarta, Indonesia
