Vibrational modes of aminothiophenol: a TERS and DFT study

Abstract

We report Tip Enhanced Raman Spectroscopy (TERS) mapping and Density Functional (DFT) calculations of aminothiophenol (ATP) grafted on a gold surface. The TERS mapping has demonstrated Raman modes of (ATP) and its dimerised derivative Dimercaptoazobenzene (DMAB). This feature confirms that the plasmon activated chemical reaction of ATP has occurred during TERS measurements. In some specific part of the samples some unidentified Raman modes are observed. We suggest that they could come from intermediate species formed during the conversion of ATP into DMAB. These modes are compared with calculated Raman spectra of some possible intermediate species. These results confirm the high potentiality of TERS measurements for nanochemistry.

Relation between plasmonic tip emission and electromagnetic enhancement evidenced in tip‐enhanced Raman spectroscopy

“…Tip‐enhanced Raman spectroscopy (TERS) offers a unique combination of the extreme sensitivity of surface‐enhanced Raman spectroscopy (SERS) and the high spatial resolution of scanning probe techniques. It has been developed at the end of the 1990s, and since then, several studies have proven its high efficiency in the field of molecular analysis, self‐assembled monolayers, surface chemistry, nanomaterials, molecular phase boundaries, and so forth.…”

Recent advances in surface plasmon-driven catalytic reactions

“…9(a)). 57 More spectral information is presented in TERS than in previous SERS. 55,56 The result reveals that PATP is dimerized into DMAB by hot electrons generated from the nanogap between the tip and the substrate.…”

Spectral fluctuation in SERS spectra of benzodiazepin molecules: The case of oxazepam

“…Numerical calculations and, in particular, DFT are essential for the interpretation of SERS spectra. [ 16,17 ] Those calculations have been carried out at the B3PW91/6‐31G* level of theory using the GAUSSIAN09 [ 18 ] suit of programs. We have calculated the structure of the isolated oxazepam molecule together with its set of harmonic frequencies.…”