A New Class of Extended Tetrathiafulvalene Cruciform Molecules for Molecular Electronics with Dithiafulvene‐4,5‐Dithiolate Anchoring Groups

Abstract

Cruciform motifs with two orthogonally oriented π-extended tetrathiafulvalenes and with differently protected thiolate end-groups are synthesized by stepwise coupling reactions. The molecules are subjected to single-molecule conductivity studies in a break-junction and to conducting probe atomic force microscopy studies in a self-assembled monolayer on gold.

Molecular Heterojunctions of Oligo(phenylene ethynylene)s with Linear to Cruciform Framework

“…Also, both of them showed higher current than that of OPE3. These results imply that the DTF, which is a strong electron donating group, can efficiently enhance the charge transport through the OPE wire, similar to what has been reported for the TTF system …”

“…This increased molecular conductance was assigned to changes in the molecular orbital energy levels relative to the Fermi level of the applied gold electrodes and a smaller HOMO–LUMO energy gap. Such extended TTF cruciform molecules were also developed with dithiafulvene‐4,5‐dithiolate anchoring groups and studied in molecular break junctions . A comprehensive study of the extended TTF cruciform molecules for molecular electronics with both the synthetic strategies and electrical transport measurements has recently been reported …”

Controlling Electrical Conductance through a π‐Conjugated Cruciform Molecule by Selective Anchoring to Gold Electrodes

“…Cruciform molecules have received significant attention because of their special structural topology and opportunities for their modulation, [5] and therefore they are considered to be promising "hub" units for the integration of different functional units in single-molecule circuits.W ithin the context of the single-molecule conductance,only three papers on cruciform molecules have appeared in the literature. [6,7] Differentiating charge-transport pathways,h owever, has been unexplored so far.T oelaborate on our concept for achieving high selectivity of anchoring sites on gold leads,w ea pply desilylation chemistry, [8] which allows trapping of molecules between two gold electrodes through in situ generated C À Au bonds.S ingle-molecule junctions formed by the CÀAu s-bonds should be energetically favored over junctions through pyridyl anchoring groups,b ecause of the larger binding strength of the covalent bond compared to the coordinative bonding between the gold and lone pair atoms. [9] Therefore,o ne can set the course for ac ontrollable conductance pathway in am olecule,f or example,w ith wellstudied pyridyl and trimethylsilyl-protected acetylene termini.…”

Tuning crystal polymorphs of a π-extended tetrathiafulvalene-based cruciform molecule towards high-performance organic field-effect transistors

“…One aim was to achieve good and tunable conducting properties by virtue of the different conjugation pathways that exist between the individual parts of the molecule [17][18][19][20][21][22][23]. These DTF-based cruciform molecular wires have demonstrated potential promising applications in molecular electronics and also provided a good platform for the investigation of the dependence of conducting properties on their molecular structures [24][25][26]. As a continuation of our work on such extended TTF compounds, it is interesting to further investigate their applications in organic electronic devices, such as OFETs, the basic component of organic circuits.…”