Relativistic TDDFT calculations including spin orbit interactions via the ZORA approximation and solvent effects were carried out on the [Mo6X8L6](2) X = Cl, Br, I; L = F, Cl, Br, I clusters. These calculations indicate that the closely spaced lowest excited states are largely centered on the cubic [Mo6X8](4+) core. Thus, our calculations and the electronic similarities with the strongly luminescent [Mo6Cl8Cl6](2), [Mo6Br8Br6](2) and [Mo6I8I6](2) clusters, suggest that the clusters [Mo6Cl8F6](2), [Mo6Br8F6](2), [Mo6I8F6](2), [Mo6I8Cl6](2) and [Mo6I8Br6](2) studied here might be also luminescent. The calculated bond energies and reactivity indexes indicate that the most labile clusters are those with axial iodide ligands. (c) 2008 Elsevier B. V. All rights reserved.