# Finding the Lowest Energy Level in the Conduction Band

Is there a theoretical way to calculate the 'edge' of the conduction band (in a pure metal lattice), or the lowest energy that an electron can have in order to conduct electricity?

I have found a document online that mentions that the energy of the conduction band is given by $X-E_C+\frac{E_G} {2}$, where $X$ is the Mulliken electronegativity, $E_C$ is the energy of free electrons of the hydrogen scale, and $E_G$ is the band gap energy. Is this correct, or a reasonable approximation, or is there even a way to find the conduction band energy without experiment?

• Unclear. Do you mean finding where the Fermi energy is in the middle of an unfilled band in a metal? – Jon Custer Jun 1 '17 at 22:36
• Perhaps my understanding of what a conduction band truly is is not clear enough - but my impression of it was that there was a minimum energy level that an electron had to reach to be a 'conducting electron' - the image that's in my head is something like this, and the energy I'm making reference to is the bottom of the rectangle denoting the conduction band. – Andi Gu Jun 1 '17 at 23:05