orbital+notations

Orbital Notations
An orbital notation is another way of depicting the electron configurations of elements, but in a more visual way.


 * Electrons:**

In orbital notation, the electron spin state is represented. An electron "spins" on its axis and is magnetic, so its direction of spin dictates its magnetism:



Each electron is represented as a 'half-arrow', and is drawn as either "spin up" or "spin down":



Because of this spin property, each orbital can only hold, at most, two oppositely-spinning electrons (an electron pair).


 * Orbitals**

Orbitals can be represented in a number of ways, including boxes, circles, lines, etc.

Here are a few examples:

Each type of sublevel (s, p, d, f) has a specific number of orbitals (1, 3, 5, and 7, respectively):

And the arrangement of these orbitals follows that of electron configuration notations.

Now for some rules.

First, electrons are all negatively charged. As they occupy a sublevel with multiple orbitals, they will not pair up unless they have to. This repulsion is the reason behind **Hund's Rule**, which essentially says to fill orbitals with electrons individually first.

Only when each orbital is half full, and more electrons are going in, will they begin to pair.



Second, because of their magnetic fields, electrons will not pair up with the same spin in an orbital. This means that every single electron in an atom will have a unique electron configuration, which is the basis of the **Pauli Exclusion Principle**.

Using orbital notation, you can now identify the energy level, sublevel, orbital, and spin state of any electron in any atom on the periodic table.