(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

This is not a homework problem. It's an example in a text book.

3 electrons.

For ##S=3/2##, we have that

$$

m_{s_1}

= m_{s_2}

= m_{s_3} = 1/2

$$

Therefore by the Pauli Exclusion principle,

$$

m_{l_1}

\neq m_{l_2}

\neq m_{l_3}

$$

and they take the values ##-1,0,1## respectively since each electron has ##l=\{0,1\}##. I understand so far. Then it says that ##^4P## and ##^4D## and ##^4F## are excluded because of this. This is where I got confused. Why is this?And why is it that ##^4S## is allowed?

2. Relevant equations

3. The attempt at a solution

We know that the ##s## quantum number is the same for all and that ##l## is the same for two of the electrons but those two can always have a different ##m_l##. So ##L=0## is the only ##L## allowed? Why?

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# Homework Help: How does the Pauli Exclusion Principle in this problem?

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