Conductivity in Divalent Metals

This mechanism of band overlap also offers another possible mechanism for the conductivity of divalent metals in addition to the possibility of s- and p-band overlap described in Chapter 3. 

Sketch of the actual Fermi surface of the noble metals. 

Simple 2-D model to explain conductivity in divalent systems. If the band in the [110] direction overlaps the energy gap in the [100] direction, there will be no effective gap in energy. If there are two electrons per atom, the Fermi energy for this band will lie in the region of overlap and electrons in the region of overlap will leave holes near the top of the band in the [100] direction. 

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Showing overlap of 2s and 2p bands that makes electrical conductivity in divalent metals possible. 

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