Gas phase acidity of substituted benzenes

► Deprotonation of C6H5X (X= H, F, Cl, OH, NH2, CN, CHO, NO2, CH3, C2H5, C2H3, C2H). ► G3B3 calculations of ΔacidH°, ΔacidG° and heats of formation of C6H5X. ► Experimental ΔacidH° of nitrobenzene is underestimated by 120 kJ/mol.