A similar but distinct picture emerges for the (111) surface. For an adsorbed H 2 molecule to detach from the surface requires 0.13 eV (5 k B T ). Dissociation may require less energy, 0.06 eV (2 k B T ) , or comparable energy, to 0.12 eV (5 k B T ) 6 to 0.31 eV (12 k B T ). Either way, both desorption and dissociation can be considered barrierless. Once dissociated, the recombination barrier is 1.36 eV (53 k B T ). For comparison, the energy barrier for a surface hydrogen atom to burrow into the subsurface layer is half, 0.66 eV (26 k B T ). Moreover, the high adsorption energies computed in this work provide a high driving force for diffusion into the bulk, which is possible from both fcc and hcp sites. Overall, the (111) is a likely candidate for non-equilibrium hydriding since dissociation is barrierless and there are many pathways to subsurface diffusion.