Adsorption and Decomposition Mechanism of 1,1-Diamino-2,2-dinitroethylene on A1（111） Surface by Periodic DFT Calculations

摘要

The adsorption of 1,1-diamino-2,2-dinitroethylene (FOX-7) molecule on the AI(I 11) surface was investigated by the generalized gradient approximation (GGA) of density functional theory (DFT). The calculations employ a supercell (4 × 4 × 2) slab model and three-dimensional periodic boundary conditions. The strong attractive forces between oxygen and aluminum atoms induce the N--O bond breaking of the FOX-7. Subsequently, the dissociated oxygen atoms and radical fragment of FOX-7 oxidize the AI surface. The largest adsorption energy is --940.5 kJ/mol. Most of charge transfer is 3.3 le from the A1 surface to the fragment of FOX-7 molecule. We also investi- gated the adsorption and decomposition mechanism of FOX-7 molecule on the AI(111) surface. The activation en- ergy for the dissociation steps of P2 configuration is as large as 428.8 kJ/mol, while activation energies of other configurations are much smaller, in range of 2.4 to 147.7 kJ/mol.