Table 2.

Overview of the bond energies (BE), reaction enthalpies (ΔH_r), proton affinities (PA), and protonated structures, calculated at the CCSD(T)-F12/VDZ-F12//ωB97X-D/aug-cc-pVTZ level of theory at 298 K.

Compound (A)	BE [kcal/mol]	ΔHr [kcal/mol]	PAcalc [kcal/mol]	PAliterature [kcal/mol]	Protonated structure
Ammonia			203.8	204a
Acetone	26.4	35.7	194.5	194a
Methyl vinyl ketone (MVK)	27.3	32.9	198.2	199.5a
Methyl ethyl ketone (MEK)	25.9	34.0	195.7	197.7a
α-Pinene	17.9	15.4	206.3	204–209b, c
β-Pinene	18.2	13.4	208.7
Camphene	18.5	15.2	207.2	205.7c
3-Carene	20.6	19.0	205.4
		27.8	196.7
Limonene	22.3	25.0	201.2
		26.0	200.2
Myrcene	20.9	20.5	204.2
Ocimene	26.0	19.1	210.7
Sabinene	20.6	8.5	215.9

BE describes the ${\text{NH}}_{\mathit{\text{4}}}^{+}$-A bond energy, ΔH_r is the reaction enthalpy of the reaction $N{H}_{\mathit{\text{4}}}^{+}A\to A{H}^{+}+N{H}_{\mathit{\text{3}}}$. We expect errors in computed proton affinities and binding enthalpies to be smaller than 1 kcal/mol. PA literature values are also given if available.

^a(Hunter and Lias, 1998).

^b(Lindinger et al., 1998b).

^c(Solouki and Szulejko, 2007).