CNDO/2 calculations of the electronic structure of the guanine-cytosine base pair: Proton transfer in excited states

A self-consistent field, all-valence electron, molecular orbital theory has been applied to the guanine-cytosine base pair. Consideration of the total energy of the system predicts that, in its ground and low-lying excited states, the base pair is stable with respect to the separate bases and that the protons in the hydrogen bonds linking the bases will each transfer from one base to the other in at least two excited states. The proton …