Density functional study of PdaCubAuc (a plus b plus c = 7) clusters: Geometry, electronic and H-2 physisorption properties

摘要

We report a systematic study of ternary PdaCubAuc clusters, with a + b + c = 7. The optimized geometries, binding energy per atom, excess binding energy, electrostatic potential surfaces and the physical adsorption behavior of H-2 were analyzed by density function theory calculation with TPSSTPSS functional and SDD basis set. PdaCubAuc clusters with more Au atoms exhibit lower binding energy per atom. The average bond distance reduces with increasing Cu content. For PdaCubAuc-H-2 clusters, the site precedence for the molecular H-2 adsorption follows the order Pd > Cu > Au. The adsorption energy correlates linearly with the elongation of H-H distance.