Addressing the Environment Electrostatic Effect on Ballistic Electron Transport in Large Systems: A QM/MM-NEGF Approach

作者:Feliciano Gustavo T; Sanz Navarro Carlos; Coutinho Neto Mauricio Domingues; Ordejon Pablo; Scheicher Ralph H; Rocha Alexandre Reily*
来源:Journal of Physical Chemistry B, 2018, 122(2): 485-492.
DOI:10.1021/acs.jpcb.7b03475

摘要

The effects of the environment in nanoscopic materials can play a crucial role in device design. Particularly in biosensors, where the system is usually embedded in a solution, water and ions have to be taken into consideration in atomistic simulations of electronic transport for a realistic description of the system. In this work, we present a methodology that combines quantum mechanics/molecular mechanics methods (QM/MM) with the nonequilibrium Greens function framework to simulate the electronic transport properties of nanoscopic devices in the presence of solvents. As a case in point, we present further results for DNA translocation through a graphene nanopore. In particular, we take a closer look into general assumptions in a previous work. For this sake, we consider larger QM regions that include the first two solvation shells and investigate the effects of adding extra k-points to the NEGF calculations. The transverse conductance is then calculated in a prototype sequencing device in order to highlight the effects of the solvent.

  • 出版日期2018-1-18
  • 单位Univ Estadual Paulista