Hi Ahmed,

I assume you're refering to the Fe2p or Co2p core levels, right? As the 2p core levels are the most frequently investigated for transition metals.

The splitting in general occurs due to the spin-orbit coupling and has nothing to do with the oxidation state. The oxidation state is determined by the valence electrons, so the 4s and 3d electrons in this case.

So to answer your question: Yes, the cobalt and iron also have multiplet splitting in the zero oxidation states (examples of spectra can be found here: https://xpsdatabase.net/iron-fe-z26-chemicals/ and here:https://xpsdatabase.net/cobalt-co-z27/)

best regards

Thorsten

@Thorsten Schultz thanks for your supportive answer and I appreciate your help.

When we talk about iron or cobalt in the zero oxidation state, we are talking about the simplest and most basic form of these metals, uncombined with another element such as oxygen or chlorine and exhibiting absolutely no multiplet splitting. Their electronic configurations are [Ar] 3d⁶ 4s² and [Ar] 3d⁷ 4s² for iron and cobalt, respectively. These configurations show that both metals are transition elements, with electrons in the d and s subshells of level 4.

Here one should be careful to not confuse multiplet splitting with spin-orbit splitting...Souad you're right that the cobalt and iron in their zero oxidation state don't show the typical multiplet structure of transition metals in higher oxidation states. However, Ahmed's question was "the zero sate shows only 1 peak in 3/2 xps or it also shows 1/2 xps peak?" And it also shows a 1/2 peak. But not due to multiplet splitting, but due to spin-orbit coupling.