集群的介电行为和子生长模式Si与N=12-30由冷电束偏移
Filip Rivic1, Andreas Lehr1, Rolf Schäfer1
1Eduard-Zintl Institute, Technical University of Darmstadt, Peter-Grünberg-Straße 8, 64287 Darmstadt, Germany.
The journal of physical chemistry. A
|March 5, 2024
概括
我们通过冷实验和量子计算探索了团的结构和介电性质. 我们发现团从紧的成长到延伸的形状,然后随着尺寸的增加成长为准球形结构.
科学领域:
- 材料科学 材料科学 材料科学
- 原子和分子物理 原子和分子物理
- 计算化学的计算化学
背景情况:
- 了解集群的结构属性关系对于材料科学至关重要.
- 以前的理论研究预测了团的形状转变,但实验验证仍然有限.
研究的目的:
- 通过实验确定冷中性集群的几何结构和介电性质.
- 研究中等大小 (N=12-30个原子) 的团的生长模式和形状转变.
主要方法:
- 在低于30K的温度下进行低温电束偏移实验.
- 使用密度函数理论进行量子化学计算.
- 在电场中旋转动态的经典轨迹模拟.
主要成果:
- 集群 (N<15) 采用基于单顶方形反 prism 的紧几何形状.
- 开始于N=15时,以循环的稳定构建块为基础,开始进行芽类生长.
- 在Si29/Si30周围观察到从前置形状转变为准球形状的过渡.
结论:
- 实验数据与有关团形状转变的理论预测一致.
- 该研究阐明了团的生长机制和结构演变.
- 理论和实验之间的偏差是通过放松效应和实验条件来解释的.
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