Multiplet and lifetime effects in the 4d photoelectron spectrum of Eu - art. no. 022713

A high-resolution 4d photoelectron spectrum of Eu has been measured. The sp ectrum reveals a rich structure reflecting multiplet splitting due to 4d-4f , 4f-4f, and spin-orbit interaction. In order to interpret the complex 4d(- 1) multiplet structure, calculations in the intermediate coupling scheme we re performed taking into account the term-dependent lifetime width of each 4d(-1) lnultiplet state. The strong influence of both the 4d-4f exchange in teraction and the term-dependent lifetime broadening on the shape of the 4d photoelectron spectrum is demonstrated. Due to the inner-shell character o f the 4d and 4f orbitals, the spectrum of atomic Eu is similar to that of E u and Gd solid samples having the same 4f(7) occupancy.