Interpolated potential energy surface and dynamics for the reactions between N(S-4) and H-3(+)((1)A(1)')

An nb initio potential energy surface for the quartet electronic state of N H3+ has been constructed at the MP2/6-31G(d,p) level of theory. The accurac y of this surface has been verified by comparison with high levels of theor y. Classical simulations of the collision of N(S-4) and H-3(+)((1)A(1)') sh owed no reaction to form NH2+ + H at thermal energies. The possibility of r eaction via surface hopping to the doublet electronic state has been invest igated by calculation of the quartet-doublet energy gap at the MRCI/6-311+G (2df,p) level of theory. No evidence of surface crossing could be found for configurations accessible at thermal energies. (C) 1998 American Institute of Physics. [S0021-9606(98)01246-X].