Research output: Contribution to Journal/Magazine › Journal article › peer-review
Research output: Contribution to Journal/Magazine › Journal article › peer-review
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TY - JOUR
T1 - Single-molecule conductance of functionalized oligoynes
T2 - length dependence and junction evolution
AU - Moreno-Garcia, Pavel
AU - Gulcur, Murat
AU - Manrique, David Zsolt
AU - Pope, Tom
AU - Hong, Wenjing
AU - Kaliginedi, Veerabhadrarao
AU - Huang, Cancan
AU - Batsanov, Andrei S.
AU - Bryce, Martin R.
AU - Lambert, Colin
AU - Wandlowski, Thomas
PY - 2013/8/21
Y1 - 2013/8/21
N2 - We report a combined experimental and theoretical investigation of the length dependence and anchor group dependence of the electrical conductance of a series of oligoyne molecular wires in single-molecule junctions with gold contacts. Experimentally, we focus on the synthesis and properties of diaryloligoynes with n = 1, 2, and 4 triple bonds and the anchor dihydrobenzo[b]thiophene (BT). For comparison, we also explored the aurophilic anchor group cyano (CN), amino (NH2), thiol (SH), and 4-pyridyl (PY). Scanning tunneling microscopy break junction (STM-BJ) and mechanically controllable break junction (MCBJ) techniques are employed to investigate single-molecule conductance characteristics. The BT moiety is superior as compared to traditional anchoring groups investigated so far. BT-terminated oligoynes display a 100% probability of junction formation and possess conductance values which are the highest of the oligoynes studied and, moreover, are higher than other conjugated molecular wires of similar length. Density functional theory (DFT)-based calculations are reported for oligoynes with n = 1-4 triple bonds. Complete conductance traces and conductance distributions are computed for each family of molecules. The sliding of the anchor groups leads to oscillations in both the electrical conductance and the binding energies of the studied molecular wires. In agreement with experimental results, BT-terminated oligoynes are predicted to have a high electrical conductance. The experimental attenuation constants beta(H) range between 1.7 nm(-1) (CN) and 3.2 nm(-1) (SH) and show the following trend: beta(H)(CN)
AB - We report a combined experimental and theoretical investigation of the length dependence and anchor group dependence of the electrical conductance of a series of oligoyne molecular wires in single-molecule junctions with gold contacts. Experimentally, we focus on the synthesis and properties of diaryloligoynes with n = 1, 2, and 4 triple bonds and the anchor dihydrobenzo[b]thiophene (BT). For comparison, we also explored the aurophilic anchor group cyano (CN), amino (NH2), thiol (SH), and 4-pyridyl (PY). Scanning tunneling microscopy break junction (STM-BJ) and mechanically controllable break junction (MCBJ) techniques are employed to investigate single-molecule conductance characteristics. The BT moiety is superior as compared to traditional anchoring groups investigated so far. BT-terminated oligoynes display a 100% probability of junction formation and possess conductance values which are the highest of the oligoynes studied and, moreover, are higher than other conjugated molecular wires of similar length. Density functional theory (DFT)-based calculations are reported for oligoynes with n = 1-4 triple bonds. Complete conductance traces and conductance distributions are computed for each family of molecules. The sliding of the anchor groups leads to oscillations in both the electrical conductance and the binding energies of the studied molecular wires. In agreement with experimental results, BT-terminated oligoynes are predicted to have a high electrical conductance. The experimental attenuation constants beta(H) range between 1.7 nm(-1) (CN) and 3.2 nm(-1) (SH) and show the following trend: beta(H)(CN)
KW - ATOMIC-FORCE MICROSCOPY
KW - NONLINEAR-OPTICAL PROPERTIES
KW - CARBON ALLOTROPE CARBYNE
KW - ANCHORING GROUPS
KW - ELECTRICAL CONDUCTANCE
KW - CHARGE-TRANSPORT
KW - WIRES
KW - ELECTRONICS
KW - RESISTANCE
KW - DERIVATIVES
U2 - 10.1021/ja4015293
DO - 10.1021/ja4015293
M3 - Journal article
VL - 135
SP - 12228
EP - 12240
JO - Journal of the American Chemical Society
JF - Journal of the American Chemical Society
SN - 0002-7863
IS - 33
ER -