Full-dimensional quantum dynamics study of isotope effects for the H2 + NH2/ND2/NHD and H2/D2/HD + NH2 reactions

Abstract

A full-dimensional quantum dynamical study for the bimolecular reactions of hydrogen molecules with amino radicals for different isotopologues is reported. The nonreactive amino radical is described by two Radau vectors that are very close to the valence bond coordinates. Potential-optimized discrete variable representation basis is used for the vibrational coordinates of the amino radical. Starting from the reaction H2 + NH2, we study the isotope effects for the two reagents separately, i.e., H2 + NH2/ND2/NHD and H2/D2/HD + NH2. The effects of different vibrational mode excitations of the reagents on the reactivities are studied. Physical explanations about the isotope effects are also provided thoroughly including the influence of vibrational energy differences between the different isotopologues and the impact of the tunneling effect.

Higher-Order Split Operator Schemes for Solving Tetratomic Reactions Using the Time-Dependent Wave Packet Method

“…The quantum scattering theory could be solved using both time-independent method and the time-dependent quantum wave packet method. Compared to the time-independent method, the time-dependent wave packet method is more popular due to its superior numerical scaling, particularly for tetratomic or polyatomic reactions. − As shown in the recent literature, full-dimensional quantum dynamic results could been obtained for quite several polyatomic systems using the multiconfigurational time-dependent Hartree (MCTDH) method , or the time-dependent wave packet method …”