Well I was wondering why some materials have a higher resistivity than others . So I took two elements randomly . I picked carbon and silicon . Carbon has lower resistivity than silicon and obviously less atomic radius . Carbon single bond with another atom of carbon is stronger than the single bond of a silicon atom with another silicon atom . So the bond length of the C-C bond is less than the bond length of Si-Si . Both Carbon and Silicon form a lattice . How is this possible? Why is Carbon a better conductor than Silicon . Does it have to do with any of the chemical properties I wrote down?
If you compare Diamond and Silicon, then the conductivity of both is poor. Both use all four bonds to connect to the next atoms. But if you consider Graphite, then its very well. The reason is the structure of the molecule. It has a big net of a system of aromatic benzene rings . Here only 3 bonds are used to connect to another C-atoms. The fourth electron is the sp2 orbitale can act to the others and transfer electrons, if a electrical field is used.