j splitting in XPS

[dgprakash]

Hi everyone, i have a doubt regarding XPS,

i read that a doublet is formed, for example in argon when an electron from 2p orbital leaves and leads to the formation of 2p 3/2 and 2p 1/2 states, and an electron with slightly lesser energy than one in the 2p orbital is emitted, giving rise to this doublet in XPS.

now what is this j splitting and how can 2p 3/2 and 1/2 states be formed, i.e what is the phenomenon happening there?

thanks in advance

[abhi2005singh]

l = 1, s = 1/2, j = |l - s|, ..., l + s = 1/2, 3/2.

Hence you have j = 1/2, 3/2 with l = 1 (p). Thus you have terms of 2p1/2 and 2p3/2.