亚稳态
四方晶系
纳米晶
结晶学
密度泛函理论
晶体结构
材料科学
带隙
多态性(计算机科学)
化学物理
纳米技术
化学
计算化学
光电子学
基因型
基因
生物化学
有机化学
作者
Bryce A. Tappan,Bonan Zhu,Patrick Cottingham,Matthew Mecklenburg,David O. Scanlon,Richard L. Brutchey
出处
期刊:Nano Letters
[American Chemical Society]
日期:2021-07-01
卷期号:21 (13): 5881-5887
被引量:16
标识
DOI:10.1021/acs.nanolett.1c02045
摘要
Structural polymorphism is known for many bulk materials; however, on the nanoscale metastable polymorphs tend to form more readily than in the bulk, and with more structural variety. One such metastable polymorph observed for colloidal Ag2Se nanocrystals has traditionally been referred to as the “tetragonal” phase. While there are reports on the chemistry and properties of this metastable polymorph, its crystal structure, and therefore electronic structure, has yet to be determined. We report that an anti-PbCl2-like structure type (space group P21/n) more accurately describes the powder X-ray diffraction and X-ray total scattering patterns of colloidal Ag2Se nanocrystals prepared by several different methods. Density functional theory (DFT) calculations indicate that this anti-PbCl2-like Ag2Se polymorph is a dynamically stable, narrow-band-gap semiconductor. The anti-PbCl2-like structure of Ag2Se is a low-lying metastable polymorph at 5–25 meV/atom above the ground state, depending on the exchange-correlation functional used.
科研通智能强力驱动
Strongly Powered by AbleSci AI