在H2中的旋转能量转换在金属表面的正形-形转换:电子和声子系统之间的相互作用
Hirokazu Ueta1, Katsuyuki Fukutani1,2
1Advanced Science Research Center, Japan Atomic Energy Agency, 2-4 Shirakata, Tokai, Ibaraki 319-1195, Japan.
The journal of physical chemistry letters
|August 20, 2023
概括
表面上的分子的正形转换率随着温度的增加而增加. 这表明旋转能量转移主要由表面电子介导,基质声子辅助.
科学领域:
- 表面科学是一门科学.
- 物理化学 物理化学
- 材料科学是一种材料科学.
背景情况:
- 了解气体表面相互作用需要澄清能量转移过程.
- 在分子吸附中旋转能量转移的理解仍然不如振动能量转移.
研究的目的:
- 对Pd上化学吸收的H2进行ortho-to-para转换的表面温度依赖性进行调查.
- 阐明分子吸附过程中控制旋转能量转移的机制.
主要方法:
- 在不同表面温度下研究了H2在Pd(210) 上的正正对等转换率.
- 分析了温度依赖性,使用一个结合基质电子和声子系统的转换模型.
主要成果:
- 随着表面温度的增加, орто-to-para转换率显著加快.
- 观察到转换率和表面温度之间的相关性.
结论:
- 在这个系统中,旋转能量转移很可能是由表面电子介导的.
- 基底声子在电子介导的旋转能量转移过程中起到辅助作用.
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