Abstract To better understand the interaction between purification gas media (Ar and N2) and the main solid inclusion α-Al2O3 in aluminum melt, first-principle calculation was employed to investigate the adsorption energy, bonding, electronic characteristics, and density of states of Ar and N2 adsorption on α-Al2O3(0001) surface. We determined that the adsorption stability of N2 is much higher than Ar, it is thus speculated N2 can serve as a better refiner to remove α-Al2O3 from molten aluminum. Also, it is found FCC sites are calculated to be energetically preferred for adsorption in these two cases. Besides, it is confirmed Ar and N2 both have obvious bonding effect at the Top site, where N2 has a large charge transfer at the Top site and forms covalent bonds. In particular, the adsorption of Ar and N2 is found mainly owing to the hybridization of Ar-3p and Al-3p orbitals, and the hybridization of N2-p and Al-p orbitals. On the other hand, with Ar adsorbed at hcp or N2 adsorbed at top site of α-Al2O3(0001) surface, the conductivity of α-Al2O3 was enhanced, and the adverse effects of α-Al2O3 to the corrosion resistance of aluminum was promoted.

中文翻译：

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从第一性原理计算研究Ar和N2在α-Al2O3(0001)表面的吸附

摘要 为了更好地理解净化气体介质（Ar 和 N2）与铝熔体中主要固体夹杂物 α-Al2O3 之间的相互作用，采用第一性原理计算研究了 Ar 的吸附能、键合、电子特性和态密度。和 N2 在 α-Al2O3(0001) 表面的吸附。我们确定 N2 的吸附稳定性远高于 Ar，因此推测 N2 可以作为更好的精炼剂从熔融铝中去除 α-Al2O3。此外，据计算，在这两种情况下，FCC 位点被计算为吸附的能量首选。此外，证实Ar和N2在Top位点都有明显的键合效应，其中N2在Top位点有较大的电荷转移并形成共价键。特别是，发现Ar和N2的吸附主要是由于Ar-3p和Al-3p轨道的杂化，以及N2-p和Al-p轨道的杂化。另一方面，Ar吸附在hcp或N2吸附在α-Al2O3(0001)表面的顶部位置，增强了α-Al2O3的导电性，促进了α-Al2O3对铝耐蚀性的不利影响.