Theoretical Investigation of the Ammonia Adsorption Process on Si(100)-2×1 Surface

The nature of the NH_(3) adsorption process on Si(100)-2×1 surface has been studied by DV-Xα(discrete variational Xαmethod)and ASED-MO(atom superposition and electron delocalization molecular orbital theory)methods.The calculated results show that NH3 is dissociatively adsorbed on the surface dangling bonds as NH_(2)(a)and H(a)un'th no activation barrier.But the further decomposion of NH_(2)(a)to NH(a)and N(a)has been found to have activation barriers of 0.87 and 1.65eV respectively.The bond geometries and electronic structures of these NH3-derived adsorbed species are described in detail.