TY - JOUR

T1 - Exploring relationships between chemical structure and molecular conductance

T2 - from α,ω-functionalised oligoynes to molecular circuits

AU - Gorenskaia, Elena

AU - Potter, Jarred

AU - Korb, Marcus

AU - Lambert, Colin

AU - Low, Paul J.

PY - 2023/7/7

Y1 - 2023/7/7

N2 - The quantum circuit rule (QCR) allows estimation of the conductance of molecular junctions, electrode|X-bridge-Y|electrode, by considering the molecule as a series of independent scattering regions associated with the anchor groups (X, Y) and bridge, provided the numerical parameters that characterise the anchor groups (a X, a Y) and molecular backbones (b B) are known. Single-molecule conductance measurements made with a series of α,ω-substituted oligoynes (X-{(C ≡ C) N}-X, N = 1, 2, 3, 4), functionalised by terminal groups, X (4-thioanisole (C 6H 4SMe), 5-(3,3-dimethyl-2,3-dihydrobenzo[b]thiophene) (DMBT), 4-aniline (C 6H 4NH 2), 4-pyridine (Py), capable of serving as ‘anchor groups’ to contact the oligoyne fragment within a molecular junction, have shown the expected exponential dependence of molecular conductance, G, with the number of alkyne repeating units. In turn, this allows estimation of the anchor (a i) and backbone (b i) parameters. Using these values, together with previously determined parameters for other molecular fragments, the QCR is found to accurately estimate the junction conductance of more complex molecular circuits formed from smaller components assembled in series.

AB - The quantum circuit rule (QCR) allows estimation of the conductance of molecular junctions, electrode|X-bridge-Y|electrode, by considering the molecule as a series of independent scattering regions associated with the anchor groups (X, Y) and bridge, provided the numerical parameters that characterise the anchor groups (a X, a Y) and molecular backbones (b B) are known. Single-molecule conductance measurements made with a series of α,ω-substituted oligoynes (X-{(C ≡ C) N}-X, N = 1, 2, 3, 4), functionalised by terminal groups, X (4-thioanisole (C 6H 4SMe), 5-(3,3-dimethyl-2,3-dihydrobenzo[b]thiophene) (DMBT), 4-aniline (C 6H 4NH 2), 4-pyridine (Py), capable of serving as ‘anchor groups’ to contact the oligoyne fragment within a molecular junction, have shown the expected exponential dependence of molecular conductance, G, with the number of alkyne repeating units. In turn, this allows estimation of the anchor (a i) and backbone (b i) parameters. Using these values, together with previously determined parameters for other molecular fragments, the QCR is found to accurately estimate the junction conductance of more complex molecular circuits formed from smaller components assembled in series.

KW - General Materials Science

U2 - 10.1039/d3nr01034a

DO - 10.1039/d3nr01034a

M3 - Journal article

VL - 15

SP - 10573

EP - 10583

JO - Nanoscale

JF - Nanoscale

SN - 2040-3364

IS - 25

ER -