DFT Calculations of Adsorption and Decomposition of N2O on Rh(100)

Adsorption and decomposition of N2O on Rh(100) surface has been investigated by density functional theory (DFT) methods with full geometry optimization, transition state search (synchronous transit methods and constrained geometry optimization), and molecular dynamics. More stable adsorption forms (lying-flat form with all three atoms of the N2O molecule interacting with the surface and "horse-like" form with two N atoms attached to the surface) have been found in the present work besides the two forms reported previously (an upright form with the terminal N atom bonding to the surface and a lying form attaching with both terminal N and O atoms to atop sites). Decomposition pathways of N2O with and without coadsorbed oxygen atoms have been identified and compared with the experimental data. The present results suggest the necessity of internal energy partitioning measurements of desorbing species to discuss the transition states of decomposition more definitely.