DFT study of 2-butyne-1,4-diol adsorption on Ni(1 1 1) or Ni(1 0 0) clusters

Density functional theory (DFT) calculation was applied to acetylene (AC) and 2-butyne-1,4-diol (BD) adsorbed on an Ni(1 1 1) or Ni(1 0 0) model cluster surface in order to elucidate the relationship between their electronic states and geometry in the adsorption process. Adsorption energy of AC calculated using BSSE correction and binding structure were in good agreement with the experimental data. The geometry and adsorption energy of AC or BD on the Ni(1 1 1) surface in the optimized adsorption condition differ from those on the Ni(1 0 0) surface. Analysis of a natural electron configuration of adsorbates before and after adsorption on Ni clusters clarified that the 2s orbital rather than other orbitals such as 2p contributed mainly to the adsorption energy.