DFT STUDY OF CO2 ADSORPTION OF CumCon(m+n=2–7) CLUSTERS.

A theoretical study was carried out of CO₂ adsorption on Cu_mCo_n(2 ≤ m + n ≤ 7) clusters using density functional method. Generally CO₂ are located at top or bridge sites, while CO₂ of Cu₂Co₄CO₂, Co₆CO₂ and Cu₂Co₅CO₂ clusters are absorbed at hollow sites. Co₃CO₂ and CuCo₂CO₂ clusters are more stable than their neighbors, while Cu₂CO₂ and Cu₆CO₂ clusters display stronger chemical stability. After adsorption, CO₂ is activated with the elongation of the C–O bond owing to electrons transfer from Cu–Co clusters to 2 π u anti-bonding orbit of CO₂. More charge transfer often corresponds to longer C–O bond and larger adsorption energy, and the chemical activity is stronger correspondingly. Magnetic and electronic properties are also discussed. [ABSTRACT FROM AUTHOR]