B3LYP predictions, hydrogen bonds

This hydrogen bonding also impacts Mossbauer spectroscopic properties as shown in Table 3. It should be noted that the use of the B3LYP method has enabled accurate predictions of the Mossbauer quadrupole splittings and isomer shifts in a wide variety of iron proteins and model systems covering all iron spin states and coordination states [8-14,23], with a theory-versus-experiment correlation coefficient R2=0.98 over an experimental range of 8.80 mm/s in 47 systems... 

Varnali and Hargittai found energies of 30 and 12 kJ/mol for the intramolecular hydrogen bond formation in 2-nitrovinyl alcohol and 2-nitro phenol, respectively [194]. They are far from 57.45 and 50.07 kJ/mol, respectively, obtained according to the classical procedure at B3LYP/6-31G level [189]. To be remembered that the isodesmic reaction technique cannot be used for activation barriers and that different energies will be predicted by different isodesmic reactions. 

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