Ionization energies of hyperlithiated Li2F molecule and LinFn−1 (n=3,4) clusters

Ionization energies (IEs) of hyperlithiated Li2F molecule and non-stoichiometric LinFn−1 (n=3,4) clusters detected in a pulsed supersonic cluster beam expanded from a laser-ablation source are reported for the first time. The IEs determined by photoionization were 3.78±0.2 for Li2F, 4.32±0.2 for Li3F2, and 4.30±0.2 eV for Li4F3. The IEs agree with theoretical IEs calculated by ab initio methods, supporting the theoretical prediction that Li2F has a hyperlithiated configuration in which the odd electron delocalizes over the two lithiums and that Li3F2 and Li4F3 have one or two odd-electron localized configurations.