Fig. 1: Potential tunneling pathways.
From: Competing quantum tunneling processes of heavy and light particles in isocyanic acid radical anions
Two possible tunneling pathways, namely, the N − H bond rotation and the NCO bond angle inversion are shown for the cis- to trans-HNCO•− isomerization reaction. Red dashed line: rotation axis of the N − H bond; red dotted arrow: direction of carbon motion during NCO bond-angle inversion.
