tagungsband - Deutsche Bunsengesellschaft für Physikalische ...

Sa 19. 5. 2007, 10.20–10.40 A
Kurzvortrag - Hauptthema 15
Theory and simulation of DNA-nanotube
contacts: geometry, electronic structure and
charge transfer
Nadine Utz 1 , Gunda Rink 1 , Thorsten Koslowski
1 , and Yong Kong 2
(1) Institute for Physical Chemistry, University
of Freiburg, Albertstrasse 23a,
D-79104 Freiburg im Breisgau
(2) Max-Planck-Institute for Metals Research,
Heisenbergstrasse 3, D-70569
Stuttgart
We address the problem of the interaction between
DNA oligomers and semiconducting nanotubes from
a theoretical and numerical perspective [1]. The
model structures have been generated by computer
simulations [2]; sample geometries are used as the
input of an electronic structure theory that is based
upon an extended Su-Schrieffer-Heeger Hamiltonian.
By analyzing the emerging potential energy surfaces,
we obtain hole transfer rates via Marcus’ theory of
charge transfer. In the presence of nanotubes, these
rates exceed those of isolated DNA single strands
by a factor of up to 10 4 . This enhancement can
be rationalized and quantified as a combination of
a template effect and the participation of the tube
within a superexchange mechanism.
[1] G. Rink, Y. Kong, T. Koslowski, Chem. Phys.
327, 98 (2006)
[2] H. Gao, Y. Kong, D. Cui, C. S. Ozkan, Nano
Lett. 3, 471 (2003)