Editing Atomic orbital (section)

== Orbital names ==
===Orbital notation and subshells===
Orbitals have been given names, which are usually given in the form:
:<math>X \, \mathrm{type} \ </math>
where ''X'' is the energy level corresponding to the [[principal quantum number]] {{mvar|n}}; '''type''' is a lower-case letter denoting the shape or [[Electron shell#Subshells|subshell]] of the orbital, corresponding to the [[angular momentum quantum number]]&nbsp;{{mvar|ℓ}}.

For example, the orbital 1s (pronounced as the individual numbers and letters: "'one' 'ess'") is the lowest energy level ({{math|1=''n'' = 1}}) and has an angular quantum number of {{math|1=''ℓ'' = 0}}, denoted as s. Orbitals with {{math|1=''ℓ'' = 1, 2 and 3}} are denoted as p, d and f respectively.

The set of orbitals for a given n and {{mvar|ℓ}} is called a ''subshell'', denoted 
:<math>X \, \mathrm{type}^y \ </math>. 
The superscript y shows the number of electrons in the subshell. For example, the notation 2p<sup>4</sup> indicates that the 2p subshell of an atom contains 4 electrons. This subshell has 3 orbitals, each with n = 2 and {{mvar|ℓ}} = 1.

===X-ray notation===
{{Main|X-ray notation}}
There is also another, less common system still used in X-ray science known as [[X-ray notation]], which is a continuation of the notations used before orbital theory was well understood. In this system, the principal quantum number is given a letter associated with it. For {{math|1=''n'' = 1, 2, 3, 4, 5, ...}}, the letters associated with those numbers are K, L, M, N, O, ... respectively.