## Ms and ML

Alexis Robles 2k
Posts: 100
Joined: Wed Sep 18, 2019 12:18 am

### Ms and ML

Is Ml always -1/2 or 1/2 on the specific electron? For Ms, what does it mean -L to L

Sally Qiu 2E
Posts: 105
Joined: Fri Aug 30, 2019 12:18 am

### Re: Ms and ML

ml is actually the quantum number that is from -l to +l. it means that ml can take on integer values from -l to +l; for example, if l was 2, then ml can be -2, -1, 0, 1, or 2. and ms is either -1/2 or +1/2

Wendy 1E
Posts: 111
Joined: Sat Aug 17, 2019 12:17 am
Been upvoted: 2 times

### Re: Ms and ML

I believe that you have ms and ml confused. Ms, which stands for the spin magnetic quantum number, is always either +1/2 or -1/2. +1/2 indicates that the electron's spin is up. -1/2 indicates that the electron's spin is down. Ml stands for the magnetic quantum number and refers to the orientation of the orbital. If the orbital is l=1 (p-orbital), the allowed values for the orientation of that orbital range from -l to l. In this case, the allowed orientation values would range from -1 to 1 (or -1,0,1).

Eva Zhao 4I
Posts: 101
Joined: Sun Sep 29, 2019 12:16 am

### Re: Ms and ML

Magnetic Quantum Number (ml) labels different orbitals or sub-shells with allowed values of l, l-1,..., 0,..., -l. For example:
l=2; ml can be -2, -1, 0, 1, 2

Spin Magnetic Quantum Number (ms) denotes the spin of an electron with values of +1/2 or -1/2, depending on if the electron is spin up or spin down.

mayarivers3I
Posts: 52
Joined: Wed Sep 18, 2019 12:18 am

### Re: Ms and ML

Ml is actually the magnetic quantum number, which refers to the orientation of the orbital, so if l=3, then ml would be -3,-2,-1,0,1,2,3. Ms is what refers to the spin, which are the two values 1/2 and -1/2.

Nathan Rothschild_2D
Posts: 131
Joined: Fri Aug 02, 2019 12:15 am

### Re: Ms and ML

I understand that ms is 1/2 or -1/2 but why is this? I understand what each value means but is there a specific reason it is always these values?

Brian J Cheng 1I
Posts: 115
Joined: Thu Jul 11, 2019 12:15 am

### Re: Ms and ML

Not really sure why ms has -1/2 and +1/2 specifically but the positive and negative values are there to represent opposite electron spins.