Single-Molecule Tip-Enhanced Raman Spectroscopy

Autor: Matthew D. Sonntag, Richard P. Van Duyne, Jordan M. Klingsporn, Tamar Seideman, Lasse Jensen, Karl A. Scheidt, Luis K. Garibay, George C. Schatz, John M. Roberts, Jon Albert Dieringer
Rok vydání: 2011
Předmět:
Zdroj: The Journal of Physical Chemistry C. 116:478-483
ISSN: 1932-7455
1932-7447
DOI: 10.1021/jp209982h
Popis: An existence proof for single-molecule tip-enhanced Raman spectroscopy (SMTERS) is given using the frequency domain approach involving the two isotopologues of Rhodamine 6G (R6G) that were previously employed for single-molecule surface-enhanced Raman spectroscopy (SMSERS). A combination of experimental and theoretical studies provides a detailed view of the isotopic response of R6G–d0 and R6G–d4 in the 600 – 800 cm–1 region. The single-molecule nature of the TERS experiment is confirmed through two lines of evidence. First, the vibrational signature of only one isotopologue at a time was observed from multiple TER spectra. Second, the spectral wandering of the 610 cm–1 mode of R6G–d0 was less than ±4 cm–1, which in turn is less than the 10 cm–1 isotopic shift so that no confusion in assignment resulted. As a consequence, the total TERS enhancement factor can now be accurately established as EFTERS = 1.0 × 1013 because only one molecule at a time is measured. Furthermore, EFTERS can be partitioned into an...
Databáze: OpenAIRE