Figure 4
From: Direct experimental observation of weakly-bound character of the attached electron in europium anion
Enlarged photoelectron spectrum of Eu− between 1.63 and 2.30 eV.
Transitions from anionic ground state to different excited states of neutral Eu atom are labeled using different letter series (Ai, Bi, …), and are indicated by different color lines. Transitions from one excited anionic state are marked with apostrophe.
