  By going beyond the Born-Oppenheimer approximation and treating the
non-adiabatic coupling terms (NACTs) as equivalent to a frictional force in a
molecular system, the classical equations of motion are solved for a test case
of H3+. Using an ab initio potential energy surface for the ground electronic
state and its NACTs with the first excited state of H3+, it is shown that (D+,
H2) collisions are slowed enough to result in trapping and formation of a
stable DH2+.
