Effect of nuclear spin symmetry in cold and ultracold reactions: D + para/ortho-H2

Abstract

We report results for reaction and vibrational quenching of the collision D with para-H _2 ( $v,j=0$ ) and ortho-H _2 ( $v,j=1$ ) at cold and ultracold temperatures. We investigate the effect of nuclear spin symmetry for barrier dominated processes ( $0\leqslant v\leqslant 4$ ) and for one barrierless case ( v = 5). We find resonant structures for energies in the range corresponding to 0.01–10 K, which depend on the nuclear spin of H _2 , arising from contributions of specific partial waves. We discuss the implications on the results in this benchmark system for ultracold chemistry.

Keywords

• cold molecules
• chemical reactions
• astrochemistry