Impact of Electrode Density of States on Transport through Pyridine-Linked Single Molecule Junctions

被引:69
作者
Adak, Olgun [1 ]
Korytar, Richard [2 ]
Joe, Andrew Y. [1 ]
Evers, Ferdinand [3 ]
Venkataraman, Latha [1 ]
机构
[1] Columbia Univ, Dept Appl Phys & Appl Math, New York, NY 10027 USA
[2] Karlsruhe Inst Technol, Inst Nanotechnol, D-76344 Karlsruhe, Germany
[3] Univ Regensburg, Inst Theoret Phys, D-93040 Regensburg, Germany
基金
美国国家科学基金会;
关键词
ENERGY-LEVEL ALIGNMENT; METAL WORK FUNCTION; CHARGE-TRANSPORT; CONDUCTANCE; CONTACTS; PHOTOEMISSION; INTERFACES; AU;
D O I
10.1021/acs.nanolett.5b01195
中图分类号
O6 [化学];
学科分类号
0703 ;
摘要
We study the impact of electrode band structure on transport through single-molecule junctions by measuring the conductance of pyridine-based molecules using Ag and Au electrodes. Our experiments are carried out using the scanning tunneling microscope based break-junction technique and are supported by density functional theory based calculations. We find from both experiments and calculations that the coupling of the dominant transport orbital to the metal is stronger for Au-based junctions when compared with Ag-based junctions. We attribute this difference to relativistic effects, which result in an enhanced density of d-states at the Fermi energy for Au compared with Ag. We further show that the alignment of the conducting orbital relative to the Fermi level does not follow the work function difference between two metals and is different for conjugated and saturated systems. We thus demonstrate that the details of the molecular level alignment and electronic coupling in metal-organic interfaces do not follow simple rules but are rather the consequence of subtle local interactions.
引用
收藏
页码:3716 / 3722
页数:7
相关论文
共 53 条
[1]   Quantum properties of atomic-sized conductors [J].
Agraït, N ;
Yeyati, AL ;
van Ruitenbeek, JM .
PHYSICS REPORTS-REVIEW SECTION OF PHYSICS LETTERS, 2003, 377 (2-3) :81-279
[2]   Single-molecule junctions beyond electronic transport [J].
Aradhya, Sriharsha V. ;
Venkataraman, Latha .
NATURE NANOTECHNOLOGY, 2013, 8 (06) :399-410
[3]   Correlating Structure, Conductance, and Mechanics of Silver Atomic-Scale Contacts [J].
Aradhya, Sriharsha V. ;
Frei, Michael ;
Halbritter, Andras ;
Venkataraman, Latha .
ACS NANO, 2013, 7 (04) :3706-3712
[4]  
Aradhya SV, 2012, NAT MATER, V11, P872, DOI [10.1038/NMAT3403, 10.1038/nmat3403]
[5]   Quantum chemistry calculations for molecules coupled to reservoirs: Formalism, implementation, and application to benzenedithiol [J].
Arnold, A. ;
Weigend, F. ;
Evers, F. .
JOURNAL OF CHEMICAL PHYSICS, 2007, 126 (17)
[6]   Spin-Polarized Electron Transport Across Metal-Organic Molecules: A Density Functional Theory Approach [J].
Bagrets, Alexei .
JOURNAL OF CHEMICAL THEORY AND COMPUTATION, 2013, 9 (06) :2801-2815
[7]   Molecular diodes enabled by quantum interference [J].
Batra, Arunabh ;
Meisner, Jeffrey S. ;
Darancet, Pierre ;
Chen, Qishui ;
Steigerwald, Michael L. ;
Nuckolls, Colin ;
Venkataraman, Latha .
FARADAY DISCUSSIONS, 2014, 174 :79-89
[8]   Ab initio molecular simulations with numeric atom-centered orbitals [J].
Blum, Volker ;
Gehrke, Ralf ;
Hanke, Felix ;
Havu, Paula ;
Havu, Ville ;
Ren, Xinguo ;
Reuter, Karsten ;
Scheffler, Matthias .
COMPUTER PHYSICS COMMUNICATIONS, 2009, 180 (11) :2175-2196
[9]   Quantitative Current-Voltage Characteristics in Molecular Junctions from First Principles [J].
Darancet, Pierre ;
Widawsky, Jonathan R. ;
Choi, Hyoung Joon ;
Venkataraman, Latha ;
Neaton, Jeffrey B. .
NANO LETTERS, 2012, 12 (12) :6250-6254
[10]  
Datta S., 2013, Quantum Transport: atom to Transistor