Long-distance charge transport through DNA. An extended hopping model

Long-distance transfer of a positive charge through DNA can be described by a hopping model. In double strands where the (A:T)(n) bridges between the guanines are short (n greater than or equal to 3), the charge hops only between guanines, and each hopping step depends strongly upon the guanine to guanine distances. In strands where the (A:T)(n) sequences between the guanines are rather long (n greater than or equal to 4), also the adenines act as charge carriers. To predict the yields of the H2O-trapping products one has to take into account not only the charge-transfer rates but also the rates of H2O-trapping reactions.