HOMO Energy Gap Dependence
of Hole-Transfer Kinetics
in DNA
- Publication date
- Publisher
Abstract
DNA consists of two type of base-pairs, G-C and A-T,
in which the
highest occupied molecular orbital (HOMO) localizes on the purine
bases G and A. While the hole transfer through consecutive Gs or As
occurs faster than 10<sup>9</sup> s<sup>–1</sup>, a significant
drop in the hole transfer rate was observed for G-C and A-T mixed
random sequences. In this study, by using various natural and artificial
nucleobases having different HOMO levels, the effect of the HOMO-energy
gap between bases (Δ<sub>HOMO</sub>) on the hole-transfer kinetics
in DNA was investigated. The results demonstrated that the hole transfer
rate can be increased by decreasing the Δ<sub>HOMO</sub> and
can be finely tuned over 3 orders of magnitude by varying the Δ<sub>HOMO</sub>