Atoms with greater than 3 electrons in the outer shell are generally characterized as:

Atoms with more than three electrons in their outer shell are typically characterized as poor conductors because they tend to have a full outer electron shell configuration, making it less likely for electrons to move freely. When atoms have a full shell or are close to being full, the electrons are held more tightly, resulting in a lack of free electrons available for conduction.

In metals, for example, the presence of a few free electrons in the outer shell is what allows for good electrical conductivity. Conversely, nonmetals or elements with higher numbers of valence electrons often form covalent bonds and therefore don’t contribute to electron flow effectively, making them poor conductors of electricity. This behavior aligns well with the principle that materials with higher electronegativity or those that have more electrons in their outer shell typically do not conduct electricity well.

On the other hand, good conductors have fewer valence electrons (like metals), while insulators and superconductors involve different mechanisms that do not apply to atoms with a greater number of outer shell electrons. Insulators, for instance, completely restrict the flow of electricity, while superconductors operate under entirely different principles at extremely low temperatures, showing perfect conductivity.