Atomic Orbitals

Starting with the energy level/shell closest to the nucleus electrons fill the different shells in order of increasing energy.

Shell 1
Shell 2
Shell 3
Shell 4
------------------------------- Increasing Energy ----------------------------->

Energy levels or shells can be divided into sub-shells, which can hold different numbers of electrons.

 
Shell 1
Shell 2
Shell 3
Shell 4
Sub-Shell
s
s
p
s
p
d
s
p
d
f

Within each sub-shell there are one or more orbitals. Each orbital can hold a maximum of two electrons (of opposite spin).

 
Shell 1
Shell 2
Shell 3
Shell 4
Sub-Shell
s
s
p
s
p
d
s
p
d
f
Number of orbitals in sub-shell
1
1
3
1
3
5
1
3
5
7
Number of electrons allowed in each orbital
2
2
2
2
2
2
2
2
2
2
Total number of electrons in each sub-shell
2
2
6
2
6
10
2
6
10
14

Explore the different atomic orbitals in 3D

s-orbitals | p-orbitals | d-orbitals