Folded network and structural transition in molten tin

• Published in: Nature communications Vol. 13; no. 1; pp. 126 - 10
• Main Authors: Xu, Liang, Wang, Zhigang, Chen, Jian, Chen, Songyi, Yang, Wenge, Ren, Yang, Zuo, Xiaobing, Zeng, Jianrong, Wu, Qiang, Sheng, Howard
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 10.01.2022; Nature Publishing Group; Nature Portfolio
• Subjects: 639/766/119/1002; 639/766/119/2795; Anomalies; ATOMIC AND MOLECULAR PHYSICS; Atomic bonding; Chemical bonds; Covalent bonds; High temperature; Humanities and Social Sciences; Liquids; MATERIALS SCIENCE; multidisciplinary; Percolation; Science; Science (multidisciplinary); Structural models; Tin
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-021-27742-2

The fundamental relationships between the structure and properties of liquids are far from being well understood. For instance, the structural origins of many liquid anomalies still remain unclear, but liquid-liquid transitions (LLT) are believed to hold a key. However, experimental demonstrations of LLTs have been rather challenging. Here, we report experimental and theoretical evidence of a second-order-like LLT in molten tin, one which favors a percolating covalent bond network at high temperatures. The observed structural transition originates from the fluctuating metallic/covalent behavior of atomic bonding, and consequently a new paradigm of liquid structure emerges. The liquid structure, described in the form of a folded network, bridges two well-established structural models for disordered systems, i.e., the random packing of hard-spheres and a continuous random network, offering a large structural midground for liquids and glasses. Our findings provide an unparalleled physical picture of the atomic arrangement for a plethora of liquids, shedding light on the thermodynamic and dynamic anomalies of liquids but also entailing far-reaching implications for studying liquid polyamorphism and dynamical transitions in liquids. Unraveling the structural origin of liquid anomalies remains a challenging topic. Xu et al. propose a folded-network structural model for molten tin and provide insights into the observed second-order-like structural transition.