Fig. 1: Photoelectron spectra at 193 nm (6.424 eV) of LnB8− (Ln = La, Pr, Tb, Tm, Yb).

a LaB8−. b PrB8−. c TbB8−. d TmB8−. e YbB8−. The blue and red bars in a and b represent computed VDEs of isomer I (C7v) and isomer II (Cs), respectively. The gray bars indicate the calculated 4f-detachment channels.