# Atomic Orbitals and Periodic Table Relationships

## Key Questions

There are many types of atomic orbital ($\text{s, p, d, f, g, h}$, …), but only the first four are occupied in the ground state of an atom.

#### Explanation:

Quantum numbers

Two quantum numbers determine the type of orbital.

The principal quantum number, $n$, determines the size of the orbital.

The secondary quantum number, $l$, determines the shape.

$\text{s}$ orbitals

For each value of $n$, there is one orbital for which $l = 0$.

These orbitals are spheres.

The higher the value of $n$, the larger the sphere.

The spheres like nested shells separated by nodes — areas where there is no electron density.

$\text{p}$ orbitals

When $n > 1$, $l$ can have any value up to $n \text{-1}$.

When $l = 1$, the orbital is called a $\text{p}$ orbital.

A $\text{p}$ orbital looks like a dumbbell.

There are three types of $\text{p}$ orbital.

Each points in a different direction.

$\text{d}$ orbitals

When $n = 3$, we can have orbitals with $l = 2$.

These are called $\text{d}$ orbitals, and there are five of them.

One looks like a dumbbell with a doughnut around the middle.

The other four $\text{d}$ orbitals look like four-leaf clovers with the leaves pointing in different directions.

$\text{f}$ orbitals

When $n = 4$, we can have orbitals with $l = 3$.

These are called $\text{f}$ orbitals, and there are seven of them.

Three of the orbitals look like a dumbbell with two donuts around the middle.

The other four orbitals look like a bundle of eight balloons tied together and pointing to the corners of a cube.