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用量子化学从头计算方法，以原子簇Ｃｕ５为模拟表面，研究了水在Ｃｕ（１００）面上不同吸附位的吸附情况，结果表明：水分子通过氧原子与表面成键，顶位是其最佳吸附位，吸附能约为７０ｋＪ／ｍｏｌ，平衡距离为０．２１３ｎｍ，氢原子远离表面．在氧原子不加极化函数时，水分子的二次轴垂直于表面时能量最低，但倾斜至５０°所需能量仅在１０ｋＪ／ｍｏｌ以内．当考虑Ｏ原子ｄ轨道的影响时，水分子倾斜时能量较低，得到了与实验相符的吸附构型．另外还研究了表面电荷对吸附体系的影响，结果表明：表面带正电荷时，水与表面间的相互作用增强，水上所转移电荷增多，Ｃｕ—Ｏ间平衡距离减小；表面带负电荷时，情况与之相反，且氢原子靠近表面时，势能曲线有最低点．
Quantum chemical ab initio method was used to study the adsorption of water on the Cu (100) surface using Cu5 as a cluster surface. The results show that the water molecule bonds with the surface via oxygen atom, Good adsorption sites, the adsorption energy is about 70kJ / mol, equilibrium distance of 0.213nm, hydrogen atoms away from the surface. In the absence of a polarization function of oxygen atoms, the water molecule has the lowest energy perpendicular to the surface, but the energy required to tilt to 50 ° is only 10 kJ / mol. When we consider the influence of d orbital of O atom, the energy of water molecule is low when it tilts, and the experimentally obtained adsorption configuration is obtained. In addition, the influence of surface charge on the adsorption system was also studied. The results show that the interaction between water and the surface is enhanced when the surface is positively charged, the charge transferred by water increases, and the equilibrium distance between Cu and O decreases. When the surface is negatively charged In the opposite case, the potential energy curve has the lowest point when the hydrogen atoms are close to the surface.