What is the correct exited state configuration of litium?

[Petar Mali]

Litium has a structure

1s^22s^1

What is the first exited state of litium?


I have some doubt? I think that it is

1s^22p^1

Is it correct or maybe

1s^23p^1

Why I'm in problem. Because wave function of hydrogen atom depends of three quantum numbers
\psi_{n,l,m} but energy depends only of one quantum number E_n. So we have degeneration. In this logic it's need to be 1s^23p^1. But I don't have hydrogen I have litium, so must be some ecranisation and of course Hund rule s and p orbitals have different energy. And I can say that

E_{n,l}=-13,6eV\frac{1}{(n-\Delta l)^2}

Thanks for your answer!

 

[Bob S]

See
http://physics.nist.gov/cgi-bin/Ionization/atom.php?element=Li
Bob S

 

[Petar Mali]

Thanks!