Vibrational properties of an adamantane monolayer on a gold surface

ORAL

Abstract

We study the vibrational properties of an adamantane monolayer on a Au(111) surface. The IR spectrum of a self-assembled monolayer of adamantane on Au(111) is measured by a newly developed infrared scanning tunneling microscopy (IRSTM) technique. We analyze the IR spectrum of this system by a density functional theory and find that the IR spectrum is severely modified by both adamantane-gold and adamantane-adamantane interactions. One of three gas-phase C-H bond stretching modes is significantly red-shifted due to the molecule-substrate interactions. The intermolecular interactions cause a suppression of the IR intensity of another gas-phase IR peak. The techniques used in this work can be applied for an independent estimate of molecule-substrate and intermolecular interactions in related diamondoid/metal-substrate systems.

*This work was supported by NSF grant No. DMR10-1006184 and U.S. DOE under Contract No. DE-AC02-05CH11231.

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Authors

  • Yuki Sakai

    • Tokyo Institute of Technology and University of California, Berkeley

  • Giang D. Nguyen

    • University of California, Berkeley

  • Rodrigo B. Capaz

    • Universidade Federal do Rio de Janeiro and University of California, Berkeley

  • Sinisa Coh

    • University of California, Berkeley and Lawrence Berkeley National Laboratory

  • Ivan V. Pechenezhskiy

    • University of California, Berkeley and Lawrence Berkeley National Laboratory

  • Xiaoping Hong

    • University of California, Berkeley

  • Michael F. Crommie

    • University of California, Berkeley and Lawrence Berkeley National Laboratory

  • Feng Wang

    • University of California, Berkeley and Lawrence Berkeley National Laboratory

  • Susumu Saito

    • Tokyo Institute of Technology

  • Steven G. Louie

    • University of California, Berkeley and Lawrence Berkeley National Laboratory

  • Marvin L. Cohen

    • University of California, Berkeley and Lawrence Berkeley National Laboratory