## Spin State

AniP_2D
Posts: 95
Joined: Sat Aug 17, 2019 12:17 am

### Spin State

Can someone please explain the concept of a spin state? I am having trouble understanding what a spin state is and what it means in regards to the orbital. Thank you.

405335722
Posts: 56
Joined: Fri Aug 30, 2019 12:16 am

### Re: Spin State

So, spin states depend on how many electrons you have in one orbital.

for example, lets say we are dealing with the P orbital which has 3 basically domains (Px, Py, and Pz) each electron can be in.

When adding electrons to a system, one must distribute each electron to Px Py and Pz BEFORE adding 2 electrons to one. All of these electrons would have the same (parallel) spin because that produces the most stable, and lowest amount of energy.

Once you start adding your 4th electron, they will always have opposite spins because they will be in Px, Py, or Pz together. Because of electron-electron repulsion, 2 electrons in the same domain in the same orbital cannot have the same spin.

I hope this sort of helps I wish I had a whiteboard or something so it would be easier to explain...

DLee_1L
Posts: 103
Joined: Sat Aug 17, 2019 12:17 am

### Re: Spin State

From my understanding, in the silver beam experiment, it was discovered that silver atoms went in two different directions because they had two different magnetic fields. These different magnetic fields are caused by the one unpaired electron spinning since a charged particle's movement causes a magnetic field. So the different magnetic fields are caused by the unpaired electron going in one of 2 directions.

Miriam Villarreal 1J
Posts: 105
Joined: Sat Aug 17, 2019 12:16 am

### Re: Spin State

The Stern and Gerlach Experiment Electron Spin was meant to utilize silver atoms which have one unpaired electron and pass them through an atom beam that goes through a magnet and arrives at a collection plate that received an upper and lower spin from two different electrons. these spins are identified as (-1/2) and (+1/2)

Hannah Romano 4D
Posts: 55
Joined: Sat Aug 24, 2019 12:18 am

### Re: Spin State

The spin state is determined by the fourth quantum number (Ms). This was originally demonstrated through shooting a Ag atom beam though a magnetic field. The Ag beam was then split into two separate electron beams, revealing that electrons within the Ag beam were not homogeneous. The differing beams revealed that the electrons had a positive or negative spin which was affected by the magnetic field. Therefore all electrons will either have a +1/2 or -1/2 spin magnetic quantum number.

Natalie C 1K
Posts: 50
Joined: Wed Sep 18, 2019 12:16 am
Been upvoted: 1 time

### Re: Spin State

I am still confused about the 1/2. Why can't we just say that one is positive and one is negative? or why isn't it a +1 and a -1?

Sanjana Borle 2K
Posts: 111
Joined: Fri Aug 09, 2019 12:15 am

### Re: Spin State

I am not sure why the 1/2 is there for the spin quantum number but it may be because the other quantum numbers are integers