caa a22 4500 463232615 CHVBK 20180405153246.0 cr unu---uuuuu 170326e20071101xx s 000 0 eng 10.1007/s10853-007-1901-6 doi (NATIONALLICENCE)springer-10.1007/s10853-007-1901-6 Multiscale model of electronic behavior and localization in stretched dry DNA [Elektronische Daten] [Ryan Barnett, Paul Maragakis, Ari Turner, Maria Fyta, Efthimios Kaxiras] When the DNA double helix is subjected to external forces it can stretch elastically to elongations reaching 100% of its natural length. These distortions, imposed at the mesoscopic or macroscopic scales, have a dramatic effect on electronic properties at the atomic scale and on electrical transport along DNA. Accordingly, a multiscale approach is necessary to capture the electronic behavior of the stretched DNA helix. To construct such a model, we begin with accurate density-functional-theory calculations for electronic states in DNA bases and base pairs in various relative configurations encountered in the equilibrium and stretched forms. These results are complemented by semi-empirical quantum mechanical calculations for the states of a small size [18 base pair poly(CG)-poly(CG)] dry, neutral DNA sequence, using previously published models for stretched DNA. The calculated electronic states are then used to parametrize an effective tight-binding model that can describe electron hopping in the presence of environmental effects, such as the presence of stray water molecules on the backbone or structural features of the substrate. These effects introduce disorder in the model hamiltonian which leads to electron localization. The localization length is smaller by several orders of magnitude in stretched DNA relative to that in the unstretched structure. Springer Science+Business Media, LLC, 2007 Barnett Ryan Department of Physics, Harvard University, 02138, Cambridge, MA, USA aut Maragakis Paul Department of Chemistry and Chemical Biology, Harvard University, 02138, Cambridge, MA, USA aut Turner Ari Department of Physics, Harvard University, 02138, Cambridge, MA, USA aut Fyta Maria Department of Physics, Harvard University, 02138, Cambridge, MA, USA aut Kaxiras Efthimios Department of Physics, Harvard University, 02138, Cambridge, MA, USA aut Journal of Materials Science Springer US; http://www.springer-ny.com 42/21(2007-11-01), 8894-8903 0022-2461 42:21<8894 2007 42 10853 https://doi.org/10.1007/s10853-007-1901-6 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s10853-007-1901-6 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Barnett Ryan Department of Physics, Harvard University, 02138, Cambridge, MA, USA aut NATIONALLICENCE 700 1- Maragakis Paul Department of Chemistry and Chemical Biology, Harvard University, 02138, Cambridge, MA, USA aut NATIONALLICENCE 700 1- Turner Ari Department of Physics, Harvard University, 02138, Cambridge, MA, USA aut NATIONALLICENCE 700 1- Fyta Maria Department of Physics, Harvard University, 02138, Cambridge, MA, USA aut NATIONALLICENCE 700 1- Kaxiras Efthimios Department of Physics, Harvard University, 02138, Cambridge, MA, USA aut NATIONALLICENCE 773 0- Journal of Materials Science Springer US; http://www.springer-ny.com 42/21(2007-11-01), 8894-8903 0022-2461 42:21<8894 2007 42 10853 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer