Ab initio study of CO adsorption on PdGa(110)

作者：Bechthold P; Jasen P V; Ardenghi J S; Gonzalez E A; Juan A^*

来源：Computational Materials Science, 2013, 71: 192-196.

DOI：10.1016/j.commatsci.2013.01.033

• PdGa
• DFT
• Intermetallic compounds
• CO adsorption

CO adsorption is analyzed using Density Functional Theory (DFT) calculations. Changes in the electronic structure of PdGa(1 1 0) surface and CO bond after adsorption are addressed. CO is located only on Pd atop geometry with a tilted configuration (9.13 degrees from the perpendicular to the surface) and no interaction with Ga is detected. The Pd-Pd bond strength decreases 54.2% as the new Pd-CO bond is formed. The C-O bond length change less than 1%, compared to the gas phase value, while its bond overlap population decrease 46.2%. The effect of CO is limited to its first Pd neighbor. Analysis of orbital interaction reveals the Pd-CO bond mainly involves s-s and s-p orbitals with less participation of Pd 4d orbitals. The computed CO vibration frequencies after adsorption shows a red shift from vacuum to ward 2013.85 cm(-1), which agrees with previous experimental data on PdGa intermetallic.