使用多体方法在LiF中的F中心缺陷的光学间隙
Ritaj Tyagi1, Abhisek Ghosal1, Vamsee K Voora1
1Department of Chemical Sciences, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005, India. vamsee.voora@tifr.res.in.
Physical chemistry chemical physics : PCCP
|August 19, 2025
概括
我们使用先进的计算方法研究了化 (LiF) 中的F中心缺陷. 我们的研究结果显示,与散装F中心相比,表面F中心的光学间隙明显较小.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 材料科学是一种材料科学.
- 计算化学是一种计算化学.
背景情况:
- F中心缺陷会影响宽带间隙固体的特性.
- 对F中心的实验和计算表征具有挑战性.
- 准确的建模需要考虑无周期性,格子扭曲和极化效应.
研究的目的:
- 为了调查 LiF.中的批量和表面 F-中心缺陷.
- 评估用于建模这些缺陷的计算高效潜力.
- 为了确定散装和表面F中心的光学间隙.
主要方法:
- 基于随机相近似 (RPA) 结合的电位与周期静电嵌入.
- 评估的单极交换相关性 (1p-XC) 和静态库伦孔选交换 (st-COHSEX) 潜力.
- 计算的光学间隙,用于 LiF 的批量和表面 F-中心缺陷.
主要成果:
- 1p-XC潜力适用于模拟散装和表面F中心缺陷.
- 大量F中心 (5.24 eV) 预测的光学间隙与高级量子化学方法和实验数据密切相匹配.
- 鉴定了表面F中心的显著较低的光学间隙 (1.85 eV),这是由于限制减少和格子放松增加而导致的.
结论:
- 1p-XC方法为研究F中心缺陷提供了准确有效的方法.
- 表面F中心与散装F中心相比,具有明显的电子特性,对材料应用有影响.
- 由于其独特的特性,进一步研究表面F中心缺陷是有必要的.
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