在Pd{111}和Pd{100}上,norbornadiene和norbornene的表面化学:一个比较的DFT研究
1MIREA - Russian Technological University, Lomonosov Institute of Fine Chemical Technologies, 86 Vernadsky Avenue, 119571, Moscow, Russian Federation. shamsiev.r@gmail.com.
Journal of molecular modeling
|October 16, 2023
概括
密度功能理论研究了与表面的norbornadiene (NBD) 和norbornene (NBE) 相互作用. 最稳定的配置和它们的移动性在Pd(111) 和Pd(100) 方面有所不同.
科学领域:
- 表面科学是一门学科.
- 计算化学的计算化学
- 材料科学 材料科学 材料科学
背景情况:
- 研究了norbornadiene (NBD) 和norbornene (NBE) 在 (111) 和 (100) 表面上的吸附.
- 探索各种吸附配置,包括内分四分-σ,内分-di-σ,π,内分-di-π,外分-σ和外分-π的NBD和NBE.
- 由于表面几何形状,突出了Pd(111) 和Pd(100) 之间的吸附配置差异.
研究的目的:
- 确定NBD和NBE在Pd(111) 和Pd(100) 表面上最稳定的吸附配置.
- 为了比较NBD和NBE在不同面上的吸附能量和分子流动性.
- 了解表面几何学对这些分子吸附行为的影响.
主要方法:
- 使用密度函数理论 (DFT) 的计算.
- 使用了Perdew-Burke-Ernzerhof (PBE) 密度函数.
- 使用了PRIRODA计划中设定的相对主义SBK有效核心潜力和TZ2P基础.
主要成果:
- 确定了NBD的endo-tetra-σ和NBE的exo-di-σ作为Pd两个方面最稳定的配置.
- 由于表面几何形状,在Pd{100}上观察到较高的吸附能量,而不是Pd{111}.
- 发现内分四σ (NBD) 和外分二σ (NBE) 配置在Pd{111}上是移动的,而NBD迁移在Pd{100}上是受阻的.
结论:
- 在表面上NBD和NBE的吸附行为强烈依赖于面的晶体方向.
- 与Pd{111}相比,Pd{100}具有更强的吸附,但配置较少.
- 两个表面之间的分子移动性大大不同,影响了潜在的表面反应和应用.
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