Fig. 2: Characterization of the self-assembled monolayers (SAMs).
From: A single atom change turns insulating saturated wires into molecular conductors
a Representative slice-through of a large-area Ag–S(CH2)14I SAM structure calculated by molecular dynamics (MD) computer simulations. b Surface coverage (ΨSAM) of Ag–S(CH2)14X SAMs as a function of X determined with angle-resolved X-ray photoelectron spectroscopy (ARXPS, filled circles) and thickness of SAM (dSAM) determined with ARXPS (filled triangles) and MD (empty triangles). c ΨSAM of Ag–S(CH2)nBr SAMs as a function of n determined with ARXPS (filled circles) and dSAM determined with ARXPS (filled triangles) and MD (open triangles). The solid and dashed blue lines are linear fits to the experimental and MD data with R2 of 0.94 and 0.99, respectively. The horizontal dashed line in panels b and c indicates the ΨSAM used in the MD calculations. d Computed MD packing energy per molecule Emol,MD and per methylene –CH2– unit Emeth,MD of Ag–S(CH2)14X SAMs as a function of X. Dashed lines are guides to the eye. The errors on the XPS data represent instrumental and fitting errors of 10% in total (see Section S4). The error bars in the MD data represent the standard deviations in the time- and molecule-averages calculated across 500 snapshots taken during the final 50 ns of 100 ns of room temperature MD of 128-molecule Ag–S(CH2)14X SAMs with the average experimental coverage of 1 nmol/cm2 on Ag(111).
