由 β-SiC 中空位-[Si + C] 协同作用引发的多级级:对电子结构动力学合的第一原理研究
Sensen Lin1,2,3, Yongheng Lu3, Yang Gao1,2
1Harbin Engineering University, College of Nuclear Science and Technology, 145 Nantong Street, Nangang District, Harbin 150001, Heilongjiang Province, China. gaoyang@hrbeu.edu.cn.
Physical chemistry chemical physics : PCCP
|February 18, 2026
概括
碳化 (SiC) 中的协同分离缺陷作为辐射损伤的种子,通过电子移位和晶格障碍引发不稳定性. 这一发现为材料降解和缺陷工程提供了新的见解.
科学领域:
- 材料科学 材料科学 材料科学
- 凝聚物质物理学 凝聚物质物理学
- 计算材料科学科学 计算材料科学
背景情况:
- 在β-碳化 (β-SiC) 中的辐射损伤导致由于原子缺陷而导致胀和变形.
- 单个空缺的作用是可以理解的,但空缺综合体的协同效应,如二次空缺,在启动级联损害方面是不清楚的.
研究的目的:
- 在照射下研究β-SiC中空位-[Si + C]复合物的协同作用.
- 了解这种缺陷单元是如何触发多层次不稳定性和材料退化.
主要方法:
- 使用了*ab initio*分子动力学 (AIMD) 模拟.
- 分析了使用碎片化电子定位函数的电子云移位.
- 研究了晶格障碍,原子移动性和声模式.
主要成果:
- 空缺-[Si + C]缺陷表现出非线性协同作用,与单个空缺不同.
- 观察到电子云移位,严重的短距离晶格障碍和抑制的原子移动性.
- 确定了一个连贯的电子结构动力学合机制,驱动损坏级联.
结论:
- 空位-[Si + C]作为一个协同缺陷核心,在β-SiC中启动多层次的损伤级联.
- 这种缺陷破坏了通过合格子应变和电子移位的周期性结合.
- 开发的电子结构动力学方法为理解共价材料的缺陷行为和指导空缺工程策略提供了一个范式.
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