[Wien] spin-up and spin-down electrons

[liuzw03 at st.lzu.edu.cn]

Dear WIENers,
Could someone tell me that how the eletrons are described in case.inst file?
In the UG, I found that the UP and DOWN eletrons have same description. e.g. 3S UP
and 3S DOWN electrons are both 3,-1,1.0, which means spin quantum number is +1.But
I have a little difficulty to understand that. Why the max. occupation is 2?? It
ought to be 1. How do we distingnish the spin UP and DOWN electrons? Not from spin
quantum number s=+1 or -1? I know my thought is wrong. But I really could not
understand that. I am waiting for your help!
 

Thanks in advance.
Best wishes 
Zaiwen