We have seen that orbital splitting happens to stabilise an electron in a Hydrogen atom. What happens in more complex atoms with more subatomic particles? Let's find out.

The Silicon Atom

Unlike Hydrogen, a Silicon Atom has a more complex makeup of sub-atomic particles.

As we can see, a Silicon Atom has 14 electrons, 14 protons and 14 neutrons.

Atomic Structure

Due to the higher number of electrons, they are able to occupy some higher states.

As we can see that the Silicon Atom has electrons all the way up to the 3p orbital. Interact with the atom to learn more.

Multiple Isolated Atoms

The inner electrons are too tightly bound to interact with other atoms, hence we will only consider the 4 valence electrons of Silicon.

These include the two 3s electrons and the two 3p electrons.

If we consider two isolated atoms, we can see that the electrons exist how we expect them to.


Hybridization refers to the combination of multiple orbitals to give rise to newer orbitals with an aggregation of the properties of its compenent orbitals.

As we can see, Hybridization causes one 3s orbital mixed with three 3p orbitals, to result in four new sp3 orbitals.

Two interacting atoms

When two Silicon Atoms are left in the same system, the valence orbitals interact with each other, and hybridize to give rise to 4 sp3 orbitals.

Interact with the atoms to learn more about the sp3 orbital.

Splitting of Hybrid Orbitals

These orbitals behave like orbitals we have encountered. For Silicon, two sp3 orbitals interact to form a bond between the atoms.

As the bond formation happens, the sp3 orbital splits, similar to how the 1s orbital split for Hydrogen.

Bonding with Multiple Atoms

Unlike a Hydrogen Atom, a Silicon Atom still has 3 electrons after forming one bond. It then looks for three other Silicon Atoms to for a bond.

These new bonds result in more splitting. Can you predict what happens when more atoms are bonded together?

A Silicon Lattice

A Silicon Lattice has a very large nummber of Silicon Atoms within it. Since each of these bonds results in a split, the energy levels are packed very close together.

Since they are very tightly packed, they appear almost as if they are continuous bands. However, upon zooming in, we can see that they are an aggregation of discrete energy levels.