2026-10-14T00:44:51Z https://api.figshare.com/v2/oai

oai:figshare.com:article/34033371 2026-09-30T15:11:21Z category_1 category_4 category_915 category_12 category_24 category_873 category_135 portal_63 item_type_6 month_year_09_2026

Resolving Coordination-Dependent Bonding Selectivity at Gold–Sulfur Interfaces Hanyu Zhang (1425250) Minghui Yu (2405236) Kai Song (107003) Changchun Wu (4887625) Chengjia Jing (22471439) Zimeng Li (5697935) Mingliang Zhang (104816) Bingchen Liu (11436559) Yongfeng Wang (139179) Daoben Zhu (1268397) Yaping Zang (1605397) Biophysics Biochemistry Physical Sciences not elsewhere classified Cell Biology Evolutionary Biology Chemical Sciences not elsewhere classified Computational Biology interfacial bonding configurations flicker noise signatures electrode electronic coupling contacts remain unclear break junction measurements assembled monolayer systems local coordination environment band model attribute deprotonated au – dependent bonding selectivity construct molecular junctions au – sh au – resolving coordination band center intact au form au au atoms upward shift undercoordinated sites molecular sensing level framework key descriptor binding selectivity Gold–sulfur interfaces underpin surface chemistry, molecular sensing and nanoelectronics, yet the atomic-scale factors governing whether thiols bind as intact Au-thiol (Au–SH) species or deprotonate to form Au-thiolate (Au–S) contacts remain unclear. Here we show at the single-molecule level that this binding selectivity is controlled by the local coordination environment of Au atoms. Using scanning tunneling microscope-break junction measurements in both solution and self-assembled monolayer systems, we construct molecular junctions with distinct Au coordination environments and resolve their interfacial bonding configurations through single-molecule conductance and flicker noise signatures. Highly coordinated Au sites favor proton-retaining Au–SH bond, whereas undercoordinated sites promote S–H bond cleavage and the formation of deprotonated Au–S bond. Density functional theory calculations and a d-band model attribute this selectivity to an upward shift of the gold d-band center at undercoordinated sites, which strengthens gold–sulfur interactions and lowers the barrier for thiol deprotonation. These results establish local Au coordination as a key descriptor of thiol binding and molecule-electrode electronic coupling, providing a molecular-level framework for tailoring gold–sulfur interfaces. 2026-09-30T00:00:00Z Text Journal contribution 10.1021/jacs.6c16493.s001 https://figshare.com/articles/journal_contribution/Resolving_Coordination-Dependent_Bonding_Selectivity_at_Gold_Sulfur_Interfaces/34033371 CC BY-NC 4.0