Table 1. Band Positions and Assignments of Thiolates in Conventional Raman and SERS Spectroscopy, Summarized from Experiments of This Studya.
| wavenumber
(cm–1) |
||||||
|---|---|---|---|---|---|---|
| conventional Raman | SERS (@Ag film substrate) | |||||
| acidic vapore | ||||||
| sample | assignments | solidb | airc | HClaq (pH 0)d | HClg | DClg |
| NTP | Region 1: aromatic ring breathing mode/C–S stretching | 1095 | 1072 | 1079 | 1077 | 1080 |
| Region 2 | 1326 (NO2) | 1332 (NO2) 1372 (N=O) 1386/1435 (Azo group) | 1330 (NO2) | 1330 (NO2) 1360 (N=O) | 1330 (NO2) 1356 (N=O) | |
| Region 3: aromatic ring stretching | 1568 | 1566 | 1561 1585 (ATP?) | 1580 | 1577 | |
| ATP | Region 1: aromatic ring breathing mode/C–S stretching | 1082 | 1071 | 1077 | 1077 | 1080 |
| Region 2 | 1362 (N=O) 1383/1430 (Azo group) | 1329 (NO2?) 1364 (N=O) | 1352 (N=O) | 1353 (N=O) | ||
| Region 3: aromatic ring stretching | 1585 | 1570 | 1571 | 1573 | 1573 | |
a
Based on the spectra, the main bands are categorized into 3 regions: Region 1: ca. 1070–1100 cm–1 (aromatic ring breathing mode/C–S stretching), Region 2: ca. 1320–1450 cm–1 (functional group), and Region 3: ca. 1560–1590 cm–1 (aromatic ring stretching mode). All band parameters were determined via Gauss fitting.
b
Data from Figure S1a,b.
c
Data from Figure S1c,d.
d
Data from Figure S5.