Abstract
Two-dimensional ordered structures of cyclohexanethiol (CHT) self-assembled monolayers (SAMs) on Au(111) formed from different solution concentrations were investigated using scanning tunneling microscopy (STM). Molecular-scale STM imaging clearly revealed the 2D phase transitions of CHT SAMs from a (2 x 4 square root of 2)R20 degrees structure to a (5 x 2 square root of 3)R35 degrees structure via a intermediate phase of a (5 x square root of 15)R25 degrees structure depending on solution concentration used for SAM fabrication. The (5 x 2 square root of 3)R35 degrees phase was observed for high concentrations, after deposition at low temperature or after long-time immersion. Based on these results, we confirmed that the molecular packing arrangement can be regarded as a fully covered SAM structure. In addition, 2D SAM formation of CHT SAMs is markedly different from that of alkanethiol SAMs, which is a result of structural dynamics of the CHT ring in the process of molecular self-assembly. The molecular-scale STM results for CHT SAMs on Au(111) can provide very useful information on understanding structural behaviors of cyclic thiol SAMs.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.