Electrons in weak periodic potential
Table of Contents
1. Materials
- Weak potential method is applicable only to materials in I-IV group of the periodic materials; alkali metals (I), alkaline earth metals (II), and transition metals (III, IV). It have the unfilled \(s\) and \(p\) shells, which behave as free valence electrons. The reason for not feeling the full potential of the atoms by these atoms are two fold:
- First, is as their electronic configuration is built upon the noble gas, [Noble gas] + (1 or 2) electrons, hence most of the nuclear attractive force is screened by the electrons lying below the energy levels. Besides these electrons can not penetrate deep into the atoms as the Pauli principles prohibits the two electrons in the same atomic orbitals.
- Second, is due to properties of the system to decrease the effective potential. As the electrons can travel almost free in the materials, every electron feels as if all other elctrons takes such position that the total atomic attractive energy decreases.