“…Namely, the spin–orbit (SO) correction to the computed D 0 (CH) has two components: one relates to the dissociation limit and involves the correction for the splitting between the 3 P 0,1,2 states of carbon atom, the other to the molecular spin–orbit interaction in the 2 Π 1/2,3/2 ground state of methylidyne. There are no particular issues with the former component, which corresponds to the weighted average of the 3 P 0,1,2 states of carbon atom of 29.59 cm −1 77–79 and lowers the C + H dissociation asymptote by the same amount. However, as pointed out in some of the previous literature, 48,58 the correct molecular spin–orbit contribution to the energy – which must include coupling to the rotational angular momentum, a.k.a.…”