Using Local Orbitals in DFT to Examine Oligothiophene Conductance Anomalies

Abstract

At the heart of a quantitatively accurate metal-molecule-metal conductance calculation, the potential profile must reflect the surface physics between the metal and vacuum. In this work, we employ a local orbital basis and calculate the conductance over a suite of Hamiltonians to examine trends within a molecular system using a rapid, self consistent scattering matrix method. As discussed above, this is justified as the tunneling barriers within the molecule largely determine the device's qualitative behavior. In this manner, the unexpectedly higher conductance experimentally measured on a four-membered oligothiophene, over its three-membered counterpart, is analyzed by calculating the conductance for a range of multi-atom displacements corresponding to a selected vibrational mode.

Open PDF

Document Details

Document Type
Technical Report
Publication Date
Jan 01, 2006
Accession Number
ADA464374

Entities

People

  • David K. Ferry
  • Gil Speyer
  • Richard Akis

Organizations

  • Arizona State University

Tags

Communities of Interest

  • Air Platforms

DTIC Thesaurus Topics

  • Crystal Lattice Vibrations
  • Density Functional Theory
  • Electrical Engineering
  • Electronics
  • Electrons
  • Engineering
  • Fermi Levels
  • Frequency
  • Fungi
  • Low Temperature
  • Molecules
  • Plane Waves
  • Solid State Electronics
  • Spectra
  • Vibration
  • Vibrational Spectra
  • Waves

Fields of Study

  • Physics

Readers

  • Neuroscience
  • Plasma Physics.
  • Quantum Chemistry

Technology Areas

  • Space