[carotis]

Hello there, newbie in quantum mechanics on board! 
So intriguing question popped up in my mind after todays class where we were treated with Slater rules and such...
Lets say we have  a wave function type psi(1,2,3) with phi A,B,C)... what would we get when we use for phiA and phi B the equal orbitals and what would be the consequence for the molecule?

[pm133]

Maybe its me not understanding but your question isnt clear.
Can you clarify what you are talking about?

[pm133]

Ok I think you are asking about what would happen if the Slater Determinant representing the single reference wavefunction contained 2 equivalent MOs.
Mathematically this is the same question as asking what happens to a determinant when two columns are equivalent. The answer is the determinant goes to zero.
The physical interpretation of this is that the wavefunction disappears because you have attempted to put two electrons in the same place with the same spin.

[carotis]

aight, that's what I've meant, thank you!