Non-adiabatic quantum reactive scattering calculations for the ultracold hydrogen exchange reaction: H + H2(v=4-8,j=0) → H + H2(v′,j′)

[Display omitted] •A non-adiabatic time-independent coupled-channel quantum dynamics methodology is applied to the fully symmetric H + H2 reaction for the first time.•The dramatic effects of the geometric phase on the ultracold rate coefficients and shape resonances are confirmed by the new non-adiabatic calculations and these effects are also shown to appear in the ultracold H + H2(v = 5–8) reactions for the first time.•A new experimentally detectable signature of the geometric phase is discovered associated with the dramatic enhancement of the shape resonance near 1 K for v = 6 which is notably absent for v = 4 and 5. A non-adiabatic quantum dynamics methodology based on a time-independent coupled-channel approach is applied to the fully symmetric H + H2(v=4-8,j=0) → H + H2(v′,j′) reaction for the first time. A two-state diabatic representation is used which includes the effects of the geometric phase (GP) and other non-adiabatic couplings. Ultracold rate coefficients are reported as a function of collision energy between 1μK and 100K. A second set of adiabatic calculations are also performed both with and without the GP. The results for v>4 are reported here for the first time and a new experimentally detectable signature of the GP is discovered associated with the dramatic appearance of an l=1 shape resonance near 1K in the total rate coefficient for v=6 which is absent for v=4 and 5.