The effective potential of interactions in crystals

This paper contains a study of the effective potential of the electron-electron interaction in a periodic crystal lattice, using the Hamiltonian of a system of ions and electrons in interaction 1], in which an effective mass is used, calculated in a many-electron approximation, and also the electron-plasmon and electron-phonon coupling constants. The smallest value is obtained for the energy and the effective potential which, besides the electron-phonon interaction, also includes the electron-plasmon interaction. It is shown that Hrivnák's results 2] are particular cases of this potential.