Superatomic Au25(SC2H5)18 Nanocluster under Pressure

The past decade haswitnessed significant advances in the synthesisand structure determination of atomically precise metal nanoclusters.However, little is known about the condensed matter properties ofthese nanosized metal nanoclusters packed in a crystal lattice underhigh pressure. Here using density functional theory calculations,we simulate the crystal of a representative superatomic gold cluster,Au-25(SR)(18) (0) (R = C2H5), under various pressures. At ambient conditions, Au-25(SC2H5)(18) (0) clustersare packed in a crystal via dispersion interactions; being a 7e superatom,each cluster carries a magnetic moment of 1 & mu;(B) orone unpaired electron. Upon increasing compression (from 10 to 110GPa), we observe the formation of intercluster Au-Au, Au-S,and S-S covalent bonds between staple motifs, thereby linkingthe clusters into a network. The pressure-induced structural changeis accompanied by the vanishment of the magnetic moment and the semiconductor-to-metaltransition. Our work shows that subjecting crystals of atomicallyprecise metal nanoclusters to high pressures could lead to new crystallinestates and physical properties.

Automated summary

The study uses density functional theory to calculate the crystal structure of a representative superatomic gold cluster under various pressures, revealing the formation of covalent bonds between clusters with increasing compression, leading to structural changes and transitions in physical properties.