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Jellium model is widely used in studies of alkali-metal clusters.In this model,the valence electrons of a cluster are delocalized in the cluster volume and fill discrete energy levels.Based on the jellium model,atomic assemblings with magic number electrons can act as superatoms,and such a superatom concept has achieved great success in explaining the stability of pure metal clusters.Superatom concept for a cluster has been extended to mimic any atom,based on electronic states and reactivity.Recently,we propose a new concept for bonding between superatoms—super valence bond(SVB),of which superatoms can share both valence pairs and nuclei for shell closure thus forming delocalized super bonding.[1] Using Li clusters as a test case,we theoretically find that metal clusters can mimic the behavior of simple molecules in electronic shells.It is found that Li14,Li10,and Li8 clusters are analogues of F2,N2,and CH4 molecules,respectively,in molecular orbital(MO)diagrams and bonding patterns.This new concept shows new insights in understanding the stability of clusters and designing the cluster-assembling materials,especially,ligand protected gold clusters,e.g.,Au 38(SR)24 and phosphine-protected Au20 nanoclsuters.[2-3] However,there are also some exceptions for some other thiolate-protected gold clusters(Au18(SR)14,Au20(SR)16 and Au24(SR)20)in disagreement with the superatom model or SVB model.Thus,we propose a new concept of superatom-network(SAN)to understand the "magic" stability of the 4e compounds.4 SAN model gives new physical insight into the chemical bonding of these 4e Au-SR compounds,which are viewed as "a network of two 2e-superatom gold cores" linked and stapled by four [Aun(SR)n+1] staple motifs.Based on the SAN model,cluster-assembling materials of Au-cluster-superatom and sulfur can be expected as extensions of SAN complexes.