Lactim-lactam tautomers relative electronic energies

Thermodynamic Quantities and Relative Electronic Energies 8 jq) for the Lactim (A) and Lactam (B) Tautomers of 2-Oxopyridine in the Vapor Phase (the Lactam Tautomer Considered as the Reference System)0... 

Both models mentioned have been used to investigate the simultaneous influence of electronic excitation and solvation (hydration) on the tautomeric equilibrium in the first two excited states of 2- and 4-oxopyri-dine tautomers (2a), (2b) and (3a), (3b). The relative stabilization energies A a,b( ) in the first two excited electronic states of the tautomers in question are given with the available experimental data in Table VIII. Comparison with experimental data can only be done for the second excited state (the appropriate experimental data for the first n - 7r state are not available). In the case of 2-oxopyridine the value of Af2a,2b( ) is estimated to be equal to -(5.4-11.7) kJ mole-1 from shifts of the absorption bands of the lactim and lactam tautomers of 2-oxopyridine and the... 

---