Au20Si12: A hollow Catalan pentakis dodecahedron

Abstract

A stable hollow AuSi cage with I symmetry has been predicted using first-principles density functional theory. The stability of the cage-like AuSi structure is verified by vibrational frequency analysis and molecular dynamics simulations. A relatively large highest occupied molecular orbital-lowest unoccupied molecular orbital gap of 1.057 eV is found. Electronic structure analysis shows that clearly p-d hybridizations between Si atoms and Au atoms are of great importance for the stability of AuSi cage. The cage-like AuSi structure may have potential applications in semiconductor industry and microelectronics.

Hydrogenated Si12Au20 cluster as a molecular sensor with high performance for NH3 and NO detection: A first-principle study

“…Our calculated cohesive energy of the Si12Au20 cluster is 3.119 eV per atom, much larger than that of Au32 cluster with Ih symme-try (2.338 eV per atom) and Si32 cluster (2.331 eV per atom), indicating the greater stability of Si12Au20 cluster than Au32 and Si32 clusters. The HOMO-LUMO gap in present work is 1.038 eV, a little smaller by 0.019 eV than that of Guo et al [41]. Meanwhile, our calculated cohesive energy is slightly larger than that of 3.069 eV per atom obtained by Guo et al [41].…”

“…The pure Si12Au20 cluster with Ih symmetry was systematically investigated by Guo et al [41]. Its configuration is shown in Fig.…”

“…Apart from the fundamental understanding of quantum effects such as the finite-size effect, the interest in Si\\Au clusters is primarily based on their applications such as molecular electronic devices, catalyst, gas sensors, etc. [28][29][30][31][32][33][34][35][36][37][38][39][40][41]. There are three main approaches to constructing these clusters: (i) Au doped Si clusters [28][29][30][31][32]: the Au doping process can stabilize particular structures (such as a fullerene-like cage) of Si clusters and lead to unusual properties, such as size selectivity, different charge transfer, large HOMO−LUMO gaps.…”

“…(ii) Si doped Au clusters [33][34][35][36][37]: the structures of Au clusters can be changed significantly, and the reactivity and catalytic activity of Au clusters affected by Si dop-ing [37]. (iii) mixed Si\\Au clusters [38][39][40][41], where very recently, Guo et al have predicted a very stable configuration of Si12Au20 cluster [41] using electronic structure methods. The stability of Si12Au20 cluster is verified by vibrational frequency analysis, molecular dynamics simu-lations, and electronic properties such as HOMO-LUMO gap [41].…”

“…(iii) mixed Si\\Au clusters [38][39][40][41], where very recently, Guo et al have predicted a very stable configuration of Si12Au20 cluster [41] using electronic structure methods. The stability of Si12Au20 cluster is verified by vibrational frequency analysis, molecular dynamics simu-lations, and electronic properties such as HOMO-LUMO gap [41]. The hollow, cage-like Si12Au20 cluster with Ih symmetry can be viewed as a hollow catalan pentakis dodecahedron, similar to the case of Cu20Si12 cluster [42], and may have potential applications in the electronics in-dustry if suitable fabrication process can be developed.…”