Abstract
From an H2 photodissociation experiment the destruction of the H(2S) metastable fragments, colliding with an H2 molecule, is shown to proceed through two competitive processes: the 2S2P mixing induced by the H2 quadrupole moment and a nonradiative process. This nonradiative process has a cross section of about 50 Å2 for thermal velocities. Its identification as H3+ production is discussed.