放射性碘分子在Cu_2O表面的吸附:第一性原理密度泛函研究（英文）

Adsorption of Radioiodine on Cu_2O Surfaces:a First-Principles Density Functional Study

采用第一性原理密度泛函计算方法和周期性平板模型系统研究了放射性碘分子在Cu_2O三个低指数表面的吸附行为。通过计算若干平衡吸附构型的结构参数和吸附能评估了不同特征吸附位的作用。构型优化计算表明所选晶面存在适度的结构弛豫。计算结果表明,与Cu_2O(110)表面相比,Cu_2O(100)和(111)晶面表现出更高的碘分子吸附反应活性。其中,表面氧原子位(O_S)和配位未饱和铜原子位(Cu_(CUS))分别为Cu_2O(100)和(111)晶面的能量最优吸附位点。此外,针对几种典型吸附结构计算分析了其电子结构信息,以进一步阐明吸附体系之间的相互作用机理。

The adsorption behavior of radioiodine （12） molecules on three different low-index surfaces of cuprous oxide （Cu2O） was systematically investigated using first-principles density functional calculations with periodic slab models. The role of typical surface adsorption sites was evaluated by calculating structural parameters of the adsorption configurations and energy features. Moderate geometry relaxation of the three low-index surfaces was observed. The results of geometry optimization and total energy calculations indicated that the Cu2O（100） and （111） surfaces exhibit higher reactivity towards 12 adsorption than the Cu2O（110） surface. The surface oxygen site （Os） was determined to be the most favorable adsorption site on the Cu2O（100） surface, while the coordinatively unsaturated copper site （Cucus） was energetically preferred on the Cu2O（111） surface. In addition, the electronic structure information for several typical configurations were explored to explain the detailed interaction mechanism of adsorbed systems.