Title | Periodic DFT Study of Acidic Trace Atmospheric Gas Molecule Adsorption on Ca- and Fe-Doped MgO(001) Surface Basic Sites. |
Publication Type | Journal Article |
Year of Publication | 2012 |
Journal | Journal of Physical Chemistry A |
Volume | 116 |
Issue | 30 |
Pagination | 7950 - 7958 |
Authors | Baltrusaitis, Jonas, Courtney Hatch, and Roberto. Orlando |
Publisher | American Chemical Society |
ISBN Number | 1089-5639 |
Keywords | iron calcium doped magnesia atm gas adsorption DFT |
Abstract | The electronic properties of undoped and Ca- or Fe-doped MgO(001) surfaces, as well as their propensity toward atm. acidic gas (CO2, SO2, and NO2) uptake was investigated with an emphasis on gas adsorption on the basic MgO oxygen surface sites, Osurf, using periodic d. functional theory (DFT) calcns. Adsorption energy calcns. show that MgO doping will provide stronger interactions of the adsorbate with the Osurf sites than the undoped MgO for a given adsorbate mol. Charge transfer from the iron atom in Fe-doped MgO(001) to NO2 was shown to increase the binding interaction between adsorbate by an order of magnitude, when compared to that of undoped and Ca-doped MgO(001) surfaces. Secondary binding interactions of adsorbate oxygen atoms were obsd. with surface magnesium sites at distances close to those of the Mg-O bond within the crystal. These interactions may serve as a preliminary step for adsorption and facilitate further adsorbate transformations into other binding configurations. Impacts on global atm. chem. are discussed as these adsorption phenomena can affect atm. gas budgets via altered partitioning and retention on mineral aerosol surfaces. [on SciFinder(R)] |