Experimental Observation of Real Time Molecular Dynamics Using Electromigrated Tunnel Junctions

Darin O. Bellisario, Albert Tianxiang Liu, Daichi Kozawa, Rebecca Han, Jasmine K. Harris, Robert Brandon Zabala, Qing Wang, Kumar V. Agrawal, Youngwoo Son, Michael S. Strano

Research output: Contribution to journalArticle

2 Citations (Scopus)

Abstract

Single molecule tunnel junctions (SMTJs) can provide important physical insights into electronic and vibrational phenomena at the molecular scale. However, observations and analysis are typically confined to sufficiently low temperatures as to suppress molecular motion and the resulting stochastic fluctuations in the tunneling current. In this work, we introduce and experimentally validate a methodology whereby a slightly higher temperature (9 K) compared to a typical SMTJ study can be used to induce sparse fluctuations in the inelastic tunneling current and provide the fingerprints of dynamics between the conformational states of the molecule. Two examples of benzene dithiol and cysteine are studied in electromigratively formed W/Au nanowire SMTJs on SiO2 at 9 K. The second-order transform of the tunneling current reveals the expected vibrational spectra. However, we show that temporal fluctuations can be analyzed using a hidden Markov Model to reveal dynamics assigned to millisecond rearrangements of the molecule, with apparent energy barriers ranging from 35 to 66 meV, consistent with theoretical predictions. The observed transitions are consistent with a model of lateral migration of the thiol-anchored molecules in an asymmetric junction. The use of temperature in SMTJs in this way can provide new insights into molecule dynamics in confined volumes and at electrode interfaces.

Original languageEnglish (US)
Pages (from-to)22550-22558
Number of pages9
JournalJournal of Physical Chemistry C
Volume121
Issue number40
DOIs
StatePublished - Oct 12 2017

Fingerprint

Tunnel junctions
tunnel junctions
Molecular dynamics
molecular dynamics
Molecules
molecules
thiols
Energy barriers
cysteine
Vibrational spectra
Hidden Markov models
Benzene
Sulfhydryl Compounds
Temperature
vibrational spectra
Nanowires
Cysteine
nanowires
benzene
methodology

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Energy(all)
  • Physical and Theoretical Chemistry
  • Surfaces, Coatings and Films

Cite this

Bellisario, D. O., Liu, A. T., Kozawa, D., Han, R., Harris, J. K., Zabala, R. B., ... Strano, M. S. (2017). Experimental Observation of Real Time Molecular Dynamics Using Electromigrated Tunnel Junctions. Journal of Physical Chemistry C, 121(40), 22550-22558. https://doi.org/10.1021/acs.jpcc.7b08228

Experimental Observation of Real Time Molecular Dynamics Using Electromigrated Tunnel Junctions. / Bellisario, Darin O.; Liu, Albert Tianxiang; Kozawa, Daichi; Han, Rebecca; Harris, Jasmine K.; Zabala, Robert Brandon; Wang, Qing; Agrawal, Kumar V.; Son, Youngwoo; Strano, Michael S.

In: Journal of Physical Chemistry C, Vol. 121, No. 40, 12.10.2017, p. 22550-22558.

Research output: Contribution to journalArticle

Bellisario, DO, Liu, AT, Kozawa, D, Han, R, Harris, JK, Zabala, RB, Wang, Q, Agrawal, KV, Son, Y & Strano, MS 2017, 'Experimental Observation of Real Time Molecular Dynamics Using Electromigrated Tunnel Junctions', Journal of Physical Chemistry C, vol. 121, no. 40, pp. 22550-22558. https://doi.org/10.1021/acs.jpcc.7b08228
Bellisario, Darin O. ; Liu, Albert Tianxiang ; Kozawa, Daichi ; Han, Rebecca ; Harris, Jasmine K. ; Zabala, Robert Brandon ; Wang, Qing ; Agrawal, Kumar V. ; Son, Youngwoo ; Strano, Michael S. / Experimental Observation of Real Time Molecular Dynamics Using Electromigrated Tunnel Junctions. In: Journal of Physical Chemistry C. 2017 ; Vol. 121, No. 40. pp. 22550-22558.
@article{14137961e18a472fb3b459d3ab864de2,
title = "Experimental Observation of Real Time Molecular Dynamics Using Electromigrated Tunnel Junctions",
abstract = "Single molecule tunnel junctions (SMTJs) can provide important physical insights into electronic and vibrational phenomena at the molecular scale. However, observations and analysis are typically confined to sufficiently low temperatures as to suppress molecular motion and the resulting stochastic fluctuations in the tunneling current. In this work, we introduce and experimentally validate a methodology whereby a slightly higher temperature (9 K) compared to a typical SMTJ study can be used to induce sparse fluctuations in the inelastic tunneling current and provide the fingerprints of dynamics between the conformational states of the molecule. Two examples of benzene dithiol and cysteine are studied in electromigratively formed W/Au nanowire SMTJs on SiO2 at 9 K. The second-order transform of the tunneling current reveals the expected vibrational spectra. However, we show that temporal fluctuations can be analyzed using a hidden Markov Model to reveal dynamics assigned to millisecond rearrangements of the molecule, with apparent energy barriers ranging from 35 to 66 meV, consistent with theoretical predictions. The observed transitions are consistent with a model of lateral migration of the thiol-anchored molecules in an asymmetric junction. The use of temperature in SMTJs in this way can provide new insights into molecule dynamics in confined volumes and at electrode interfaces.",
author = "Bellisario, {Darin O.} and Liu, {Albert Tianxiang} and Daichi Kozawa and Rebecca Han and Harris, {Jasmine K.} and Zabala, {Robert Brandon} and Qing Wang and Agrawal, {Kumar V.} and Youngwoo Son and Strano, {Michael S.}",
year = "2017",
month = "10",
day = "12",
doi = "10.1021/acs.jpcc.7b08228",
language = "English (US)",
volume = "121",
pages = "22550--22558",
journal = "Journal of Physical Chemistry C",
issn = "1932-7447",
publisher = "American Chemical Society",
number = "40",

}

TY - JOUR

T1 - Experimental Observation of Real Time Molecular Dynamics Using Electromigrated Tunnel Junctions

AU - Bellisario, Darin O.

AU - Liu, Albert Tianxiang

AU - Kozawa, Daichi

AU - Han, Rebecca

AU - Harris, Jasmine K.

AU - Zabala, Robert Brandon

AU - Wang, Qing

AU - Agrawal, Kumar V.

AU - Son, Youngwoo

AU - Strano, Michael S.

PY - 2017/10/12

Y1 - 2017/10/12

N2 - Single molecule tunnel junctions (SMTJs) can provide important physical insights into electronic and vibrational phenomena at the molecular scale. However, observations and analysis are typically confined to sufficiently low temperatures as to suppress molecular motion and the resulting stochastic fluctuations in the tunneling current. In this work, we introduce and experimentally validate a methodology whereby a slightly higher temperature (9 K) compared to a typical SMTJ study can be used to induce sparse fluctuations in the inelastic tunneling current and provide the fingerprints of dynamics between the conformational states of the molecule. Two examples of benzene dithiol and cysteine are studied in electromigratively formed W/Au nanowire SMTJs on SiO2 at 9 K. The second-order transform of the tunneling current reveals the expected vibrational spectra. However, we show that temporal fluctuations can be analyzed using a hidden Markov Model to reveal dynamics assigned to millisecond rearrangements of the molecule, with apparent energy barriers ranging from 35 to 66 meV, consistent with theoretical predictions. The observed transitions are consistent with a model of lateral migration of the thiol-anchored molecules in an asymmetric junction. The use of temperature in SMTJs in this way can provide new insights into molecule dynamics in confined volumes and at electrode interfaces.

AB - Single molecule tunnel junctions (SMTJs) can provide important physical insights into electronic and vibrational phenomena at the molecular scale. However, observations and analysis are typically confined to sufficiently low temperatures as to suppress molecular motion and the resulting stochastic fluctuations in the tunneling current. In this work, we introduce and experimentally validate a methodology whereby a slightly higher temperature (9 K) compared to a typical SMTJ study can be used to induce sparse fluctuations in the inelastic tunneling current and provide the fingerprints of dynamics between the conformational states of the molecule. Two examples of benzene dithiol and cysteine are studied in electromigratively formed W/Au nanowire SMTJs on SiO2 at 9 K. The second-order transform of the tunneling current reveals the expected vibrational spectra. However, we show that temporal fluctuations can be analyzed using a hidden Markov Model to reveal dynamics assigned to millisecond rearrangements of the molecule, with apparent energy barriers ranging from 35 to 66 meV, consistent with theoretical predictions. The observed transitions are consistent with a model of lateral migration of the thiol-anchored molecules in an asymmetric junction. The use of temperature in SMTJs in this way can provide new insights into molecule dynamics in confined volumes and at electrode interfaces.

UR - http://www.scopus.com/inward/record.url?scp=85031321219&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85031321219&partnerID=8YFLogxK

U2 - 10.1021/acs.jpcc.7b08228

DO - 10.1021/acs.jpcc.7b08228

M3 - Article

VL - 121

SP - 22550

EP - 22558

JO - Journal of Physical Chemistry C

JF - Journal of Physical Chemistry C

SN - 1932-7447

IS - 40

ER -