A quantum-mechanical study of the influence of excitation and solvation on the tautomeric equilibrium of tetrazole

Abstract

The stability of both tautomeric forms of tetrazole in the gas phase and the influence of an aqueous environment on the shift of the tautomeric equilibria in the ground and excited states have been investigated using quantum-mechanical methods. In the gas phase the most stable tautomer in the ground state was 2H-tetrazole, whereas in aqueous solution it was the 1H-tautomer. The influence of the aqueous environment on spectral characteristics of both tautomers has been estimated. Theoretical calculations of the tautomeric equilibrium in the ground and excited states, as well as of the stabilization energies of the excited tetrazole molecule in water, have also been carried out.