A DFT study of adsorption and decomposition of nitroamine molecule on Mg(001) surface

The adsorption and dissociation mechanism of NH2NO2 on the Mg surface have been investigated by the generalized gradient approximation of density functional theory. Calculations employ a supercell (3 x 3 x 3) slab model and three-dimensional periodic boundary conditions. The strong attractive force between oxygen and Mg atoms induces the N-O bond of the NH2NO2 to decompose. The dissociated oxygen atoms and radical fragment of NH2NO2 oxidize readily Mg atoms. The largest adsorption energy is -860.5 kJ/mol. The largest charge transfer is 3.76 e from surface Mg atoms to fragments of NH2NO2. The energy barriers of N-O bond dissociation are in a range of 11.6-36.5 kJ/mol. The adsorption energy of NH2NO2 on the Mg surface compensates the energy needed for the N-O bond dissociation.