Conduction Electrons

Similar to the concept of free electrons, it is also important to cover the topic of conduction electrons in similar detail. Although they show different behaviour in the case of semiconductors and metallic solids, they hold equal importance as free electrons due to the difference in statistical methods used to measure their concentrations in a given solid material. In this article, we will discuss the topic of conduction electrons in great detail while going through the most important concepts related to it. But before we proceed, let us first know what conduction electrons are and their fundamental meaning.

What Are Conduction Electrons?

Conduction electrons are referred to as the electron present in metallic solids and semiconductors that are partially filled with energy bands. There are almost no electrons present in the conduction band of semiconductors and other such materials at little to no temperature. However, they are likely to appear with a slight increase in temperature. This is due to the power of illumination and the addition of impurities under external influences. 

There is always a certain level and concentration of conduction electrons in the case of metallic solids. This becomes even more frequent when the given concentration is high. In such cases, conduction electrons in metallic solids usually occupy all possible states with lesser energies. It is easy to interpret these by using the concepts of frequency of collisions. 

However, things are different in the case of semiconductors. The gas is well interpreted by a conventional statistical method where the concentration of conduction electrons is relatively less. In the case of metallic solids, conduction electrons are found in the format of a degenerated liquid, commonly known as Fermi liquid. 

Therefore, the concentration of conduction electrons in the case of semiconductors and metallic solids is entirely different from each other.

Difference between Conduction Electrons and Free Electrons

The application of free electrons depends on the given circumstances. They are not tired of any items or molecules and shift from one place to another due to the insurance of the given electric field. 

On the other hand, conduction electrons jump from the orbits of one atom to another but stay attached to the conductor. They are not firmly attached to any group of atoms or molecules. 

However, this random movement by conduction electrons usually picks up a direction in an electric field. This gives us an idea of the net movement of charges across the cross-section of an electric field. Therefore, it would be right to conclude that conduction electrons always remain the same without increasing or decreasing the concentration of charges or electrons.

Free electrons are usually stuck in metallic solids because they do not possess sufficient energy to excite themselves out of them. Thus, they need more time to do so, which is often recognised as the photoelectric effect.

Conduction Electrons in Metallic Solids

In the case of metallic solids, conduction electrons are not restricted to any particular atoms, which means that they are non-localised. On the other hand, each atom contributes towards building one single such electron in the case of conventional metals. 

In such cases, it is possible to neglect conduction electrons and the mutual interaction they share to the very first approximation. It is because most stationary items protect these interactions. It is also why conduction electrons are treated as an ideal gas. 

The concentration of conduction electrons in metallic solids is much more than the concentration of other categories of particles in any given conventional gas. Therefore, it is not always possible to use conventional statistical norms to analyse conduction electrons. In fact, several other statistical methods, such as Fermi Dirac statistics, are used to calculate the concentration of conduction electrons in metals.

Conclusion

Conduction electrons are the set of electron orbitals that are generally present on the outermost shells of the atom. It can either be a semiconductor or a conductor. 

Although the behaviour of conduction electrons differs depending on the material, they are a lot different from free electrons and other similar classes of electrons. They play an important role as we study their significance with respect to electric fields.