1. Why are the valence electrons the most important on influencing the electrical properties of silicon? Why are the core electrons not as important? Why are the core electrons important to distinguish Si, Gs, GaAs and others?
2. What is the energy of the is level in an isolated silicon? (Use the Slater Tables) At what assumed spacing between adjacent atoms would you expect the is energy levels to begin to broaden into a band in a highly compressed silicon crystal? How about a hydrogen crystal?