中国物理B ›› 2024, Vol. 33 ›› Issue (4): 47102-047102.doi: 10.1088/1674-1056/ad1d4e
Yong-He Deng(邓永和)1,†, Bei Chen(陈贝)2, Qing-Hua Qi(祁清华)2, Bing-Bing Li(李兵兵)2, Ming Gao(高明)1, Da-Dong Wen(文大东)1, Xiao-Yun Wang(王小云)2,‡, and Ping Peng(彭平)3
Yong-He Deng(邓永和)1,†, Bei Chen(陈贝)2, Qing-Hua Qi(祁清华)2, Bing-Bing Li(李兵兵)2, Ming Gao(高明)1, Da-Dong Wen(文大东)1, Xiao-Yun Wang(王小云)2,‡, and Ping Peng(彭平)3
摘要: To date, there is still a lack of a comprehensive explanation for caged dynamics which is regarded as one of the intricate dynamic behaviors in amorphous alloys. This study focuses on Pd82Si18 as the research object to further elucidate the underlying mechanism of caged dynamics from multiple perspectives, including the cage's lifetime, atomic local environment, and atomic potential energy. The results reveal that Si atoms exhibit a pronounced cage effect due to the hindrance of Pd atoms, resulting in an anomalous peak in the non-Gaussian parameters. An in-depth investigation was conducted on the caged dynamics differences between fast and slow Si atoms. In comparison to fast Si atoms, slow Si atoms were surrounded by more Pd atoms and occupied lower potential energy states, resulting in smaller diffusion displacements for the slow Si atoms. Concurrently, slow Si atoms tend to be in the centers of smaller clusters with coordination numbers of 9 and 10. During the isothermal relaxation process, clusters with coordination numbers 9 and 10 have longer lifetimes, suggesting that the escape of slow Si atoms from their cages is more challenging. The findings mentioned above hold significant implications for understanding the caged dynamics.
中图分类号: (Molecular dynamics calculations (Car-Parrinello) and other numerical simulations)