对Ag111-p4×4) -O阶段结构的新见解:高分辨率STM和DFT研究
B V Andryushechkin1,2, T V Pavlova1, V M Shevlyuga1
1Prokhorov General Physics Institute of the Russian Academy of Sciences, Vavilov str. 38, 119991 Moscow, Russia. andrush@kapella.gpi.ru.
Physical chemistry chemical physics : PCCP
|December 18, 2023
概括
扫描道显微镜和密度函数理论揭示了两个不同的Ag{111) -p{4 × 4) -O相,挑战了现有的模型. 该研究发现,在该阶段内,当地的氧气覆盖率存在显著差异.
科学领域:
- 表面科学是一门学科.
- 材料科学 材料科学 材料科学
- 物理化学 物理化学
背景情况:
- 111) -p4 × 4) -O阶段是一个已知的表面结构.
- 之前的模型,如Ag6星团模型,已被提出来解释其原子排列.
研究的目的:
- 重新检查Ag{111) -p{4 × 4) -O阶段的原子结构.
- 调查公认的Ag6模型的有效性.
- 为了确定阶段内的局部氧气覆盖分布.
主要方法:
- 扫描道显微镜 (STM) 用于高分辨率成像.
- 密度函数理论 (DFT) 用于理论计算.
- 在STM图像中对偏差依赖性的分析.
主要成果:
- 发现了两种不同的表面相,表现出相同的p{\displaystyle p{\mathrm {4}} × 4} 周期.
- 证明公认的Ag6模型与高分辨率的STM数据不一致.
- 有证据表明,当地的氧气覆盖范围显著不均,范围从1/8到1/2ML不等.
结论:
- 对于Ag{111) -p{4 × 4) -O相的公认的Ag6模型是不正确的.
- 4×4) 阶段不是一个单一的,统一的结构,而是表现出可变的氧气覆盖.
- 需要新的模型来准确地描述原子排列和氧气分布.
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