The structure and orientation of calixresorcinarene receptor adsorbate self-assembled monolayers (SAMs) on Au(111) were studied with atomic force microscopy (AFM). In molecularly-resolved images, two hexagonal periodicities with lattice constants of 11.6 ± 0.4 and 4.2 ± 0.2 Å, respectively, were observed. These two periodicities could be observed separately as well as simultaneously by changing the imaging force. The experimentally determined distances are assigned to different parts of the adsorbates; the 11.6 Å repeat distance is related to the lattice of the calixresorcinarene recognition sites of the adsorbates, while the smaller repeat length fits well with the interchain distance of a closest packing of alkyl chains. These measurements confirm our previous assumption regarding the high degree of order of the calixresorcinarene SAMs on gold.
Schönherr, H., Vancso, G. J., Huisman, B. H., van Veggel, F. C. J. M., & Reinhoudt, D. (1997). An atomic force microscopy study on self-assembled monolayers of resorcinarene adsorbates on Au(111). Langmuir, 13(6), 1567-1570. https://doi.org/10.1021/la961084l