## Electron Spin

WUng_1D
Posts: 50
Joined: Sat Aug 24, 2019 12:16 am

### Electron Spin

When drawing the arrows for the orbitals, why do we have the draw the arrows going up first and then the arrows going down after

Alfred Barrion 2H
Posts: 100
Joined: Sat Jul 20, 2019 12:16 am

### Re: Electron Spin

We draw arrows going up first because each electron must enter an empty orbital first before going into the same orbital because of repulsion (two electrons repel). By putting the arrows up before down, it shows how we can minimize repulsion in a specific element.

Ryan 1K
Posts: 101
Joined: Fri Aug 09, 2019 12:15 am

### Re: Electron Spin

The arrows are different directions to indicate the opposite electron spins. Although the electrons aren't actually spinning up and down, we can indicate their spins with up and down arrows. As to why we write the up arrow before the down arrow, I believe it is arbitrary seeing as how the direction of the arrows is arbitrary as well (up and down don't refer to the actual directions).