Source: Science and Technology Daily
The reporter learned from the Hefei Research Institute of the Chinese Academy of Sciences that the research group of Researcher Wu Zhikun of the Institute of Solid State Physics of the Academy of Sciences cooperated with Professor Jin Rongchao of Carnegie Mellon University in the United States to build appropriate inter-cluster/internal weak interaction forces through the selection of ligands, and successfully resolved the cluster structure of Au144 (SR)60, which has plagued the scientific community for many years and is the "holy grail" of gold nanocluster structure research. The relevant results were recently published in the sub-journal of Science.
Gold is usually yellow, but more than 150 years ago, the famous British scientist Faraday synthesized a bright burgundy gold sol. This burgundy gold sparked interest and ushered in the era of nanoparticle research. Why is the gold sol red? How do individual gold atoms stack up in solution to grow into gold nanocrystals? ...... These problems have stimulated people's enthusiasm for research, but they have also plagued people for a long time. Metal nanoclusters between gold atoms and jinna crystals provide ideal materials for understanding these problems, especially nanoclusters (nanocrystals) that are near the "critical size" of the transition from nanoclusters to nanocrystals, which are particularly favored. However, the analysis of its structure is a challenging task.
The researchers used single crystal X-ray diffraction to solve the structure of Au144(SR)60, confirmed that the cluster consisted of a metal core of the three-shell layer (Au12-Au42-Au60) and 30 SR-Au-SR "staple" structural units on the surface, and revealed the weak interaction forces between clusters/internals, providing strong evidence for their view that the inter-cluster/internal weak interaction forces play an important role in crystal growth, and also for subsequent difficult metal nanoclusters/. The single crystal growth of nanocrystals provides a reference and reference.
In addition, the researchers also found through variable temperature single crystal X-ray diffraction that the gold-gold bonds of different lengths in the Au144 (SR)60 cluster have different variable temperature elasticity, of which the gold-gold bond with a bond length of 2.88 angstroms has better thermal ductility than the gold-gold bond of other bond lengths, which explains why the metal has better thermal ductility relative to other common solids from the perspective of chemical bonds. (Reporter Wu Changfeng)