In this work, we report ab initio calculations, based on density functional (DFT) theory and second order Møllar–Plesset (MP2) perturbation methodology to investigate the relative stability of Si 8 H 8−n Li n (n=0–8) clusters. The work presented in this paper is aimed at to investigate if lithium atoms are better candidates over hydrogen atoms to saturate the dangling bonds while stabilizing a three dimensional (3D) silicon cluster, such as S 8 , so that it can promote the same point group symmetry as in its carbon analog. Such a concept was first hypothesized by Zdetsis (J. Chem. Phys. 127 (2007) 214–306) while attempting benzene symmetry in Si 6 Li 6 ring. The cubic Si 8 cluster has been saturated both by H and Li atoms, and the sequential replacement of hydrogen by lithium atom is marked by the decrease in binding energy, HOMO–LUMO gap, ionization potential, and chemical hardness inferring that hydrogen atoms are preferable candidates over lithium atoms for the stabilization of 3D Si 8 cluster. In addition, it is observed that both H and Li atoms, induce cubane symmetry (O h ) in 3D Si 8 cluster provided that they undergo terminal bondings with Si atoms. On the other hand, Li atoms placed at the bridge sites are found to distort the structure of Si 8 from the cubane symmetry.