Table 1.

Gas-phase enthalpies (−ΔH) of adduct formation with Lewis bases; values in kJ·mol⁻¹ at 298 K unless otherwise noted.

Lewis Base	G4*-Calculated a	Experimental	Δ(Calc. − Exp.)
Trimethylamine	126.4	111.3 ± 8.4 b [36,37,38]	15.1
Dimethyl ether	62.4	57.1 ± 0.8 [39]	5.3
Tetrahydrofuran	72.5	70.3 ± 0.8 [40]	2.2
Tetrahydropyran	69.0	64.5 ± 0.8 [40]	4.5
Ethyl acetate	55.9	53.6 ± 2.9 [41]	2.3
Trimethylphosphine	66.1	79.1 [42,43]	−13.0
Tetrahydrothiophene	37.9	21.8 ± 1.7 [44]	16.1

^a see text and Section 3.2;^b at 273 K.