Au2Si20: a honeycomb-shaped structure with short Au−Au single bond at the centre coordinated by twelve Si5 pentagons and reinforced by strong Au−Si interactions and aromaticity

Anion photoelectron spectroscopy and quantum chemistry calculations of TaSi16−/0 clusters: global minimum fullerene-like cage structure, bonding and superatom properties

TaSi₁₆⁻ has a fullerene-like cage structure, σ + π double delocalized bonding patterns, a superatom closed-shell electron configuration, and aromaticity.

Structural Evolution and Electronic Properties of TaSin-/0 (n = 2-15) Clusters: Size-Selected Anion Photoelectron Spectroscopy and Theoretical Calculations

The structural evolution and electronic properties of TaSi_n^-/0 (n = 2-15) clusters are explored using anion photoelectron spectroscopy accompanied by quantum chemical calculations. The Ta atom in TaSi_n^-/0 is inclined to interact with more Si atoms and has high coordination numbers. The theoretical calculations show that TaSi₂^-/0 have trianglur structures and TaSi₃^-/0 adopt pyramid structures, while the geometries of TaSi_n^-/0 (n = 4-7) are all exohedral structures dominated by bipyramid-based configurations with the Ta atom face-capping the Si_n motifs. TaSi₈^-/0 and TaSi_9-10^- have boat-shaped geometries, whereas TaSi_9-10 neutrals adopt bipyramid-based geometries instead of boat-shaped ones. TaSi₁₁^- and TaSi₁₂ are confirmed as the critical size of transiting from exohedral to endohedral structures for anionic and neutral clusters, respectively. TaSi_12-15^-/0 have pentagonal or hexagonal prism-based geometries. Natural population analysis shows that the electron transfers from Si_n skeletons to Ta atom. The second-order energy differences (Δ₂E) and incremental binding energy (ΔE^I) values exhibit strong odd-even alternations, suggesting that the TaSi_n-odd^-/0 clusters are more stable than the adjacent TaSi_n-even^-/0 ones, except that TaSi_12^-/0 are more stable than TaSi_11^-/0 and TaSi_13^-/0.

Structural evolution from exohedral to endohedral geometries, dynamical fluxionality, and structural forms of medium-sized anionic and neutral Au2Sin (n = 8–20) clusters

Au₂Si₈⁻, Au₂Si₉⁻, Au₂Si₁₃⁻, Au₂Si₁₅⁻, _Au2Si₁₇⁻ anions and Au₂Si₁₃, Au₂Si_{14, Au2}Si₁₇ neutrals show dynamical fluxionality. In addition, the odd-even alternations of chemical stabilities are observed in the anionic and neutral Au₂Si_n clusters.