On the photoelectron spectrum of Li4−

The most stable structure for Li4− is found to be the rhombus. Electron detachment from this structure does not seem able to fully explain the experimental photoelectron spectrum. The computed results are consistent with those of Rao, Jena, and Ray, who have proposed that the experimental spectrum consists of a superposition of detachment from the Li4− rhombus (2B2u) and tetrahedron (4A1), forming the singlet and triplet states of Li4, respectively.