Abstract Ethanol adsorption on CaO (0 0 1) surface at low coverage is studied using Density Functional Theory (DFT) calculations with van der Waals corrections. We investigated the CaO surface in its rock salt structure. The more favorable sites for C2H5OH adsorption are on one (or two) Ca cations bonding the O atom from ethanol, while H atom bond to surface oxygens with an adsorption energy of −1.12 (−1.14) eV. The distance of ethanol to surface is in the range of 2.3–2.5 A. The molecule presents a strong elongation of the adsorbed O H group being 53% (51%) larger that its molecular distance. Bond order analysis shows that distances and BO are similar for Ca Omolecule and Ca Osurface. A charge transfer occurs from O atom of the 2nd layer to Ca ions at 1st layer and the molecular O atom gain some charge, while H loses charge towards surface oxygen and from this to the rest of the surface.

中文翻译：

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CaO(001)表面乙醇吸附的DFT研究

摘要 使用具有范德华修正的密度泛函理论 (DFT) 计算研究了低覆盖率下 CaO (0 0 1) 表面上的乙醇吸附。我们研究了其岩盐结构中的 CaO 表面。C2H5OH 吸附的更有利位点是在一（或两个）Ca 阳离子上与乙醇中的 O 原子键合，而 H 原子以 -1.12 (-1.14) eV 的吸附能与表面氧键合。乙醇与表面的距离在 2.3-2.5 A 的范围内。该分子表现出吸附 OH 基团的强伸长率，比其分子距离大 53% (51%)。键序分析表明，Ca Omolecule 和 Ca Osurface 的距离和 BO 相似。电荷从第二层的 O 原子转移到第一层的 Ca 离子，分子 O 原子获得一些电荷，