Silicon–metal clusters: Nano-templates for cluster assembled materials

Abstract The structure, cohesive energy and electronic properties of MSi n clusters were studied by first-principles calculations as a function of size ( n ) and species (M). We investigated 168 different clusters, containing from 1 to 14 Si atoms together with one transition metal atom among 12 different elements: Ti, Zr, Hf, V, Nb, Ta, Ni, Pd, Pt, Cu, Ag, Au. Clusters with n = 7, 10, 12 appear as local maxima in cohesive energy, independently of the metal involved. This, together with our previous findings for MSi n (containing 12 other transition metal elements), establishes a systematic behavior. For most metals, MSi 12 and MSi 10 (the smallest endohedral species) are highly symmetric and exhibit local (with respect to their neighbors in size) stability. Thus, besides practically all MSi 12 clusters (exceptions being HfSi 12 , ZrSi 12 ), also some MSi 10 such as VSi 10 , NiSi 10 , PdSi 10 , NbSi 10 and AgSi 10 , are promising candidates as building blocks for cluster assembled materials. Electronic properties of structurally equivalent clusters depend markedly on the transition metal involved, providing the means to tailor pre-defined properties when designing extended phases.