Spectroscopy of molecular junctions

Abstract

In this tutorial review we present in detail recent studies in which molecular junctions were simultaneously probed by conductance measurements and optical spectroscopy methods such as electroluminescence (EL) and Raman scattering. The advantages of combining these experimental approaches to improve our understanding of charge transport through molecular junctions are discussed and routes for future developments are suggested.

Photophysical Properties of Oligo­(phenylene ethynylene) Iridium(III) Complexes Functionalized with Metal‐Anchoring Groups

“…[29][30][31][32][33] In this work, we present the synthesis and characterization of a series of monocationic photoluminescent Ir III complexes (Ir1-Ir4, Figure 1), which incorporate conjugated ligands of different molecular length and are functionalized with suitable anchoring groups for their integration into metallic molecular junctions. [34,35] The new compounds result from the combination of iridium(III) bis-cyclometallated 2-phenylpyridine complexes with four different diimine π-conjugated ligands (1)(2)(3)(4). Ligands 1-4 are 1,10-phenanthroline (phen) derivatives symmetrically functionalized at their 3-and 8-positions with 1-(Sacetylthio)-4-phenyl and pyridine terminal groups, which are connected to the phen core by phenylethynyl spacers of different length.…”

“…[1][2][3][4] On this basis, the conductance of some single molecules contacted between metallic electrodes could be optically switched through light-triggered isomerization. [5][6][7][8][9] On the other hand, molecular-dipole changes have a deep influence on the electronic structures of contacted molecules.…”

Electroluminescence in Molecular Junctions: A Diagrammatic Approach

“…They have potential applications to single molecular electronic devices 3 . Recently optical spectroscopy of molecular junctions has become an active area of research [4][5][6][7][8][9][10][11][12][13][14][15] . Since molecular junctions are in a current carrying state, its optical response differ from that of an isolated molecule 16 .…”

Shaping the Atomic‐Scale Geometries of Electrodes to Control Optical and Electrical Performance of Molecular Devices

“…We subsequently examined the atomic‐scale geometries of electrodes employing Raman scattering spectroscopy, since it is sensitive to the electrodes' atomic‐scale geometry . Figure a shows the schematic of Raman scattering measurement system.…”

“…We subsequently examined the atomic-scale geometries of electrodes employing Raman scattering spectroscopy, since it is sensitive to the electrodes' atomic-scale geometry. [14,28,29,44,45] Figure 3a shows the schematic of Raman scattering measurement system. The incident laser was focused onto the molecular junction via a lens from the top of the MCBJ chip and the scattered light was collected directed to the spectrometer with the same lens.…”