Supplementary materials

Data of TPD; optimized structures of the water chains at the step; discussion of the predicted vibrational frequency; optimized monolayer structures of water; analysis of the optimized structures of water monolayer; Population analysis; optimized structures of hydroxyl and water; structures of water monolayer with hydroxyls; predictions of \ch from the DFT optimized structures; area analysis of the experimental spectra; structural analysis of water monolayer with hydroxyls.

TPD（程序升温脱附，Temperature Programmed Desorption）数据；台阶处水链的优化构型；预测振动频率的相关讨论；水单层膜的优化构型；水单层膜优化构型的分析；布居分析（Population analysis）；羟基与水的优化构型；含羟基的水单层膜结构；基于DFT（密度泛函理论，Density Functional Theory）优化构型的ch预测；实验光谱的面积分析；含羟基水单层膜的结构分析。