title: HOMO energy gap dependence of hole-transfer kinetics in DNA.
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(9) s(-1), 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(HOMO)) on the hole-transfer kinetics in DNA was investigated. The results demonstrated that the hole transfer rate can be increased by decreasing the Δ(HOMO) and can be finely tuned over 3 orders of magnitude by varying the Δ(HOMO).
authors.affiliation: The Institute of Scientific and Industrial Research (SANKEN), Osaka University, Mihogaoka 8-1, Ibaraki, Osaka 567-0047, Japan.
authors.forename: Kiyohiko
authors.initials: K
authors.lastname: Kawai
authors.forename: Mitsuo
authors.initials: M
authors.lastname: Hayashi
authors.forename: Tetsuro
authors.initials: T
authors.lastname: Majima
mesh_terms: D004247:DNA / Q000138:chemical synthesis / Q000737:chemistry*; D007700:Kinetics
chemical_list: D004247:DNA