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Title: Enhanced coupling through π-stacking in imidazole-based molecular junctions
We demonstrate that imidazole based π–π stacked dimers form strong and efficient conductance pathways in single-molecule junctions using the scanning-tunneling microscope-break junction (STM-BJ) technique and density functional theory-based calculations. We first characterize an imidazole-gold contact by measuring the conductance of imidazolyl-terminated alkanes ( im-N-im , N = 3–6). We show that the conductance of these alkanes decays exponentially with increasing length, indicating that the mechanism for electron transport is through tunneling or super-exchange. We also reveal that π–π stacked dimers can be formed between imidazoles and have better coupling than through-bond tunneling. These experimental results are rationalized by calculations of molecular junction transmission using non-equilibrium Green's function formalism. This study verifies the capability of imidazole as a Au-binding ligand to form stable single- and π-stacked molecule junctions at room temperature.  more » « less
Award ID(s):
1764256
PAR ID:
10160770
Author(s) / Creator(s):
; ; ; ; ; ; ; ;
Date Published:
Journal Name:
Chemical Science
Volume:
10
Issue:
43
ISSN:
2041-6520
Page Range / eLocation ID:
9998 to 10002
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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