Isotopic substitution affects excited state branching in a DNA duplex in aqueous solution

Abstract

Changing the solvent from H₂O to D₂O dramatically affects the branching of the initial excited electronic states in an alternating G·C DNA duplex into two distinct decay channels. The slower, multisite PCET channel that deactivates more than half of all excited states in D₂O becomes six times weaker in H₂O.