The qualitative behaviour of the resulting surface-to-surface distances, extracted from the MD simulations, is in good agreement with experimental results reported by Gauvin et al. on films from 7 nm-diameter GNPs with alkanethiol ligands with 12-14 carbon units. A slope of 1.1 Å per CH 2 unit was found in our simulations, close to an increase of 1.0 Å per CH 2 unit observed in experiments (see Figure ). Our surface-to-surface distances are also comparable to large-scale, coarse-grained MD simulations of nanocluster assemblies with alkanethiols of different chain length by Liu et al. Their icosahedral nanoclusters consisted of 20 flat Au(111) facets and the ligands were simulated by a united atom approach where CH 2 , CH 3 , and SH groups were treated as beads, and a Lennard-Jones potential was used to simulate their interaction. They observed an increase of the interparticle distance of 1.0 Å per CH 2 unit, similar to our simulations and the experiment. They found an interparticle distance of 15.7 Å for 12T, which is comparable with what we found (see Figure ). Compared to the experimental distances by Gauvin et al., however, we as well as Liu et al. underestimate the interparticle distance. For 12T, for example, we found a surface-to-surface distance of 14.0 Å , while they measured distances of 19.0 Å. We will now discuss differences between alkanemonothiolate and alkanedithiolate sandwich structures to understand why our simulated distances of the alkanedithiolates agree well