Table 3. Enthalpies at 0 K (ΔH_0 K in kcal mol^–1 for Transition States Relative to Reactants (C₂H + HX → C₂H₂ + X)^a.

donor	CBSb	δT(Q)	δCORE	δREL	δDBOC	δZPVE	total
HNCO	4.06	–0.19	0.14	–0.14	0.23	–1.90	2.19
trans-HONO	6.38	–0.96	0.03	0.23	–0.01	–0.76	4.91
C2H4	1.74	–0.11	–0.01	–0.01	0.02	–1.17	0.47
CH3OHc	1.49	–0.28	0.01	–0.21	0.11d	–1.28	–0.27

^aδ denotes various corrections. See the Theoretical Methods section for details.

^bCBS denotes the CCSD(T)/CBS relative energy.

^cCH₃OH + C₂H → CH₃O + C₂H₂.

^dDBOC correction not included in the final total.