Ändra sökning
RefereraExporteraLänk till posten
Permanent länk

Direktlänk
Referera
Referensformat
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Annat format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annat språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf
Determination of the Configuration of a Single Molecule Junction by Inelastic Electron Tunneling Spectroscopy
KTH, Skolan för bioteknologi (BIO), Teoretisk kemi.
KTH, Skolan för bioteknologi (BIO), Teoretisk kemi.
Visa övriga samt affilieringar
2010 (Engelska)Ingår i: The Journal of Physical Chemistry C, ISSN 1932-7447, E-ISSN 1932-7455, Vol. 114, nr 11, s. 5199-5202Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

First-principles calculations for inelastic electron tunneling spectroscopy (IETS) of a single 1,3-propanedithiol molecule covalently bound to gold electrodes are presented. Inelastic electron tunneling spectra of the single molecule junction with different contact geometries and molecular orientations at the interface are simulated. It is demonstrated that the delicate variation in the configuration of the single molecule junction caused by separating the two electrodes call result in significant changes in the inelastic electron tunneling spectral profile of the junction. The two Most probable configurations of the molecular junction formed in the experiment (Nano Lett. 2008, 8, 1673) are theoretically identified, and the experimental IET spectra are correctly assigned.

Ort, förlag, år, upplaga, sidor
2010. Vol. 114, nr 11, s. 5199-5202
Nyckelord [en]
transport
Nationell ämneskategori
Fysikalisk kemi
Identifikatorer
URN: urn:nbn:se:kth:diva-19318DOI: 10.1021/jp101428dISI: 000275708600061Scopus ID: 2-s2.0-77949796797OAI: oai:DiVA.org:kth-19318DiVA, id: diva2:337365
Anmärkning
QC 20110114Tillgänglig från: 2010-08-05 Skapad: 2010-08-05 Senast uppdaterad: 2017-12-12Bibliografiskt granskad
Ingår i avhandling
1. Theoretical Modeling of Intra- and Inter-molecular Charge Transport
Öppna denna publikation i ny flik eller fönster >>Theoretical Modeling of Intra- and Inter-molecular Charge Transport
2012 (Engelska)Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
Abstract [en]

This thesis focuses on theoretical study of charge transportproperties in molecular systems. The understanding of the transportprocess and mechanism in molecular systems is essential forthe design of new functional molecular materials and molecularelectronic devices. The molecular junctions and organic molecularcrystals have been used as the model systems to highlight the usefulnessof theoretical modelling. A molecular junction is a system that consists ofone or several molecules sandwiched between two electrodes.The charge transport in molecular junctions is a very complex processthat is affected by the interaction between molecules and electrodes,the surroundings, as well as electron-electron (e-e) andelectron-phonon (e-p) couplings. When the molecule-electrode couplingis strong, the transport process can be very quick. If the e-p couplingis weak, the inelastic tunneling has only negligible contributions to thetotal current and the elastic electron tunneling plays the dominant role.Furthermore, the hopping process becomes dominant in the case of strong e-pcoupling, for which the geometric relaxation of the molecule needsto be considered. In this thesis, we have examined these three kinds oftransport processes separately.

The first studied system is a molecular junction consisting of aromaticallycoupled bimolecules. Its elastic electron tunneling property is simulatedusing Green's functional theory at density functional theory level.The dependence of the conductance of bimolecular junctions on the vertical distances,horizontal distances and the tilt angles has been systematically studied. Theinelastic electron tunneling spectra (IETS) of molecular junctions have beencalculated for several systems that were experimentally measured with conflictingresults and controversial assignments. Our calculations provide the reliableassignments for the experimental spectra and revealed unprecedented detailsabout the molecular conformations within the junctions under different conditions.It demonstrates that a combined theoretical and experimental IETS study is capableof accurately determining the structure of a single molecule inside the junction.The hopping process is a dominant charge transfer process in organic molecularcrystals. We have studied the charge transport ability of four kinds of n-typeorganic semiconductor materials to find out the related structure-to-propertyrelationship. It is done by adopting the quantum charge transfer rate equationcombined with the random walk approach.

Ort, förlag, år, upplaga, sidor
Stockholm: KTH Royal Institute of Technology, 2012. s. x, 68
Serie
Trita-BIO-Report, ISSN 1654-2312 ; 2012:15
Nyckelord
charge transport, molecular junction, organic molecular materials, Green's function, first-principles simulation
Nationell ämneskategori
Fysikalisk kemi
Forskningsämne
SRA - Transport
Identifikatorer
urn:nbn:se:kth:diva-94103 (URN)978-91-7501-371-8 (ISBN)
Disputation
2012-06-05, FA32, AlbaNova University Center, Roslagstullsbacken 21, Stockholm, 10:00 (Engelska)
Opponent
Handledare
Forskningsfinansiär
TrenOp, Transport Research Environment with Novel Perspectives
Anmärkning
QC 20120515Tillgänglig från: 2012-05-15 Skapad: 2012-05-07 Senast uppdaterad: 2012-05-15Bibliografiskt granskad

Open Access i DiVA

Fulltext saknas i DiVA

Övriga länkar

Förlagets fulltextScopus

Personposter BETA

Luo, Yi

Sök vidare i DiVA

Av författaren/redaktören
Lin, Li-LiSong, Xiu-NengLuo, Yi
Av organisationen
Teoretisk kemi
I samma tidskrift
The Journal of Physical Chemistry C
Fysikalisk kemi

Sök vidare utanför DiVA

GoogleGoogle Scholar

doi
urn-nbn

Altmetricpoäng

doi
urn-nbn
Totalt: 112 träffar
RefereraExporteraLänk till posten
Permanent länk

Direktlänk
Referera
Referensformat
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Annat format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annat språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf