EFFECT OF SCANDIUM ON HIDROGEN DISSOCIATION ENERGY AT MAGNESIUM SURFACE: AB INITIO DFT STUDY

I Wayan Sutapa (Department of Chemistry, Faculty of Mathematics and Natural Sciences, Unpatti)
Ria Armunanto (Department of Chemistry, Faculty of Mathematics and Natural Sciences, Austrian-Indonesian Centre for Computer Chemistry, Universitas Gadjah Mada)
Karna Wijaya (Department of Chemistry, Faculty of Mathematics and Natural Sciences, Austrian-Indonesian Centre for Computer Chemistry, Universitas Gadjah Mada)

Indonesian Journal of Chemistry
Vol 10, No 2 (2010)

The dissociative chemisorption of hydrogen on both pure and Sc-incorporated Mg(0001) surfaces have been studied by ab initio density functional theory (DFT) calculation. The calculated dissociation energy of hydrogen molecule on a pure Mg(0001) surface (1.200 eV) is in good agreement with comparable theoretical studies. For the Sc-incorporated Mg(0001) surface, the activated barrier decreases to 0.780 eV due to the strong interaction between the molecular orbital of hydrogen and the d metal state of Sc. This could explain the experimentally observed improvement in absorption kinetics of hydrogen when transition metals have been introduced into the magnesium materials.