Information on mass chains and nuclides available on this website:

WWW TUNL

¹³Li is not observed in the 4.8 GeV proton bombardment of a uranium target: the cross section is < / ~ 0.2 μb (BO74A). ¹³Li is predicted to have an atomic mass excess of 61.56 MeV: it is then unstable for breakup into ¹²Li + n and ¹¹Li + 2n by 0.6 and 4.5 MeV, respectively (TH74). The modified mass equation leads to a calculated amu of 60.34 MeV: ¹³Li would then be stable with respect to breakup into ¹²Li + n by 0.7 MeV, assuming the amu of ¹²Li to be 52.94 MeV, but would be unstable with respect to ¹¹Li + 2n by 3.3 MeV (JE75). See also (TH72K, BE75Q).