The xTB-optimised structures for the three homoleptic cages with 1 DBF , 2 Py and 2 Th were both reoptimised and their SPEs calculated at the DFT level of theory (PBE0/Def2-SVP/D3BJ/PCM(DMSO)). Disappointingly, these new computed data suggested the homoleptic systems would be favoured in both instances by more than 50 kJ mol -1 (Table ), contrary to the experimental outcomes.