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### spin up and spin down

Posted: Wed Oct 16, 2019 11:53 pm
I don't understand why when it is spin up and down it is a +1/2 or a -1/2. I understand that the + and - are indications of the direction but I don't understand what the 1/2 means.

### Re: spin up and spin down

Posted: Thu Oct 17, 2019 12:54 am
someone correct me if I'm wrong but I think Lavelle said that the numbers are arbitrary, they're just used to represent one state or the other.

### Re: spin up and spin down

Posted: Thu Oct 17, 2019 1:46 am
Yes, that is correct, the numbers do not play an important role in this situation. The only thing we need to pay attention to is the sign indicating the spin, the 1/2 value does not matter.

### Re: spin up and spin down

Posted: Thu Oct 17, 2019 2:04 am
The numbers are arbitrary so you don't need to worry all too much about it. Just focus on the sign of the number and you will know if the electron spins up or down.

### Re: spin up and spin down

Posted: Thu Oct 17, 2019 2:13 am
We just need to know what the signs mean in case of the electron spinning upwards or downwards, not putting an emphasis on the charge of the +1/2 or -1/2. They act as placeholders when looking for the orbitals using the numbers in parenthesis such as (2, 1, 0, 1/2).

### Re: spin up and spin down

Posted: Thu Oct 17, 2019 10:57 pm
The numbers are only arbitrary and we only need to focus on whether the electron is spinning upward or downward. The value +- 1/2 don't really mean any specific values in electron spinning.

### Re: spin up and spin down

Posted: Fri Oct 18, 2019 5:16 pm
There are actually reasons for the +/- 1/2 labels that are beyond the scope of this class. The most important parts are the opposite signs and its application to the Pauli Exclusion Principle

### Re: spin up and spin down

Posted: Fri Oct 18, 2019 5:40 pm
In this topic, the sign plays a huge role rather than the integer since its only arbitrary. The positive and negative sign represents their spin.