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Title: First-principles approach for the charge transport characteristics of monolayer molecular electronic devices : application to the hexanedithiolate devices.

Abstract

We report on the development of an accurate first-principles computational scheme for the charge transport characteristics of molecular monolayer junctions and its application to hexanedithiolate (C6DT) devices. Starting from the Gaussian basis set density-functional calculations of a junction model in the slab geometry and corresponding two bulk electrodes, we obtain the transmission function using the matrix Green's function method and analyze the nature of transmission channels via atomic projected density of states. Within the developed formalism, by treating isolated molecules with the supercell approach, we can investigate the current-voltage characteristics of single and parallel molecular wires in a consistent manner. For the case of single C6DT molecules stretched between Au(111) electrodes, we obtain reasonable quantitative agreement of computed conductance with a recent scanning tunneling microscope experiment result. Comparing the charge transport properties of C6DT single molecules and their monolayer counterparts in the stretched and tilted geometries, we find that the effect of intermolecular coupling and molecule tilting on the charge transport characteristics is negligible in these devices. We contrast this behavior to that of the {pi}-conjugated biphenyldithiolate devices we have previously considered and discuss the relative importance of molecular cores and molecule-electrode contacts for the charge transport in those devices.

Authors:
 [1];  [1];  [2];
  1. (California Institute of Technology, Pasadena, CA)
  2. (Korea Institute for advanced Study, Seoul, Korea)
Publication Date:
Research Org.:
Sandia National Laboratories
Sponsoring Org.:
USDOE
OSTI Identifier:
951714
Report Number(s):
SAND2006-1139J
TRN: US200913%%24
DOE Contract Number:
AC04-94AL85000
Resource Type:
Journal Article
Resource Relation:
Journal Name: Proposed for publication in Physical Review B.
Country of Publication:
United States
Language:
English
Subject:
42 ENGINEERING; CHARGE TRANSPORT; SEMICONDUCTOR JUNCTIONS; ORGANIC SULFUR COMPOUNDS; DENSITY FUNCTIONAL METHOD; GREEN FUNCTION

Citation Formats

Tahir-Kheli, Jamil, Goddard, William A., III, Kim, Yong-Hoon, and Schultz, Peter Andrew. First-principles approach for the charge transport characteristics of monolayer molecular electronic devices : application to the hexanedithiolate devices.. United States: N. p., 2006. Web.
Tahir-Kheli, Jamil, Goddard, William A., III, Kim, Yong-Hoon, & Schultz, Peter Andrew. First-principles approach for the charge transport characteristics of monolayer molecular electronic devices : application to the hexanedithiolate devices.. United States.
Tahir-Kheli, Jamil, Goddard, William A., III, Kim, Yong-Hoon, and Schultz, Peter Andrew. Sun . "First-principles approach for the charge transport characteristics of monolayer molecular electronic devices : application to the hexanedithiolate devices.". United States. doi:.
@article{osti_951714,
title = {First-principles approach for the charge transport characteristics of monolayer molecular electronic devices : application to the hexanedithiolate devices.},
author = {Tahir-Kheli, Jamil and Goddard, William A., III and Kim, Yong-Hoon and Schultz, Peter Andrew},
abstractNote = {We report on the development of an accurate first-principles computational scheme for the charge transport characteristics of molecular monolayer junctions and its application to hexanedithiolate (C6DT) devices. Starting from the Gaussian basis set density-functional calculations of a junction model in the slab geometry and corresponding two bulk electrodes, we obtain the transmission function using the matrix Green's function method and analyze the nature of transmission channels via atomic projected density of states. Within the developed formalism, by treating isolated molecules with the supercell approach, we can investigate the current-voltage characteristics of single and parallel molecular wires in a consistent manner. For the case of single C6DT molecules stretched between Au(111) electrodes, we obtain reasonable quantitative agreement of computed conductance with a recent scanning tunneling microscope experiment result. Comparing the charge transport properties of C6DT single molecules and their monolayer counterparts in the stretched and tilted geometries, we find that the effect of intermolecular coupling and molecule tilting on the charge transport characteristics is negligible in these devices. We contrast this behavior to that of the {pi}-conjugated biphenyldithiolate devices we have previously considered and discuss the relative importance of molecular cores and molecule-electrode contacts for the charge transport in those devices.},
doi = {},
journal = {Proposed for publication in Physical Review B.},
number = ,
volume = ,
place = {United States},
year = {Sun Jan 01 00:00:00 EST 2006},
month = {Sun Jan 01 00:00:00 EST 2006}
}
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