A grand unified model for liganded gold clusters

Abstract

A grand unified model (GUM) is developed to achieve fundamental understanding of rich structures of all 71 liganded gold clusters reported to date. Inspired by the quark model by which composite particles (for example, protons and neutrons) are formed by combining three quarks (or flavours), here gold atoms are assigned three ‘flavours' (namely, bottom, middle and top) to represent three possible valence states. The ‘composite particles' in GUM are categorized into two groups: variants of triangular elementary block Au3(2e) and tetrahedral elementary block Au4(2e), all satisfying the duet rule (2e) of the valence shell, akin to the octet rule in general chemistry. The elementary blocks, when packed together, form the cores of liganded gold clusters. With the GUM, structures of 71 liganded gold clusters and their growth mechanism can be deciphered altogether. Although GUM is a predictive heuristic and may not be necessarily reflective of the actual electronic structure, several highly stable liganded gold clusters are predicted, thereby offering GUM-guided synthesis of liganded gold clusters by design.

Au13(8e): A secondary block for describing a special group of liganded gold clusters containing icosahedral Au13 motifs

“…For example, with using the three Au "flavors" b, m, and t, I 79 can be rewritten as According to electron counting protocols of the GUM, each of the two surface gold atoms bonded with SR is assigned to transfer 0.5e valence electron to the staple motif. 29 Thus, each of the 12 surface gold atoms of the icosahedral Au 13 core is assigned to have 0.5e valence electron. Since the central gold atom of the icosahedral Au 13 core has 1e valence electron and the net charge of [Au 25 (SR) 18 ] 1-is -1, the total valence electrons of the icosahedral Au 13 core is 12 × 0.5e + 1e + 1e = 8e, and the icosahedral Au 13 core is in the I 79 valence state.…”

[Au12(SR)6]2−, As Smaller 8‐Electron Gold Nanocluster Retaining an SP3‐Core. Evaluation of Bonding and Optical Properties from Relativistic DFT Calculations

“…Moreover, 1 can be viewed as another addition to the examples of clusters based on Au 4 networks,, with four Au 4 motifs fused together. Hence, additionally to the SP 3 ‐Au 8 view, 1 can also be considered as a network of four 2e‐Au 4 fused motifs contributing to the libraries of predicted Au 4 (AuL) n nanoclusters by Cheng and Jang …”

Highly Stretchable Graphene Fibers with Ultrafast Electrothermal Response for Low‐Voltage Wearable Heaters

“…Lightweight wileyonlinelibrary.com helical structures of GFs are completely different from the highly aligned structure of wet-spun GFs, [42] which generally results in a low fracture strain. The GF heaters are fabricated by twist-spinning of thermally annealed graphene films, which significantly improves the fracture strain up to 70% with a toughness 22.45 MJ m −3 .…”