Кононов / 10
.pdf
( ex) – Raman scattering cross-section (cm2)ex – excitation frequency
E0 – incident beam irradiance ni – number density in state i
exponential – Boltzmann factor for state i
Ei
R α ( ex ) ex4 E0nie kT
( ex) - target area presented by a molecule for scattering
Process |
Cross-Section of |
(cm2) |
absorption |
UV |
10-18 |
absorption |
IR |
10-21 |
emission |
Fluorescence |
10-19 |
scattering |
Rayleigh |
10-26 |
scattering |
Raman |
10-29 |
scattering |
RR |
10-24 |
scattering |
SERRS |
10-15 |
scattering |
SERS |
10-16 |
Adenine
Tip Enhanced Raman
Tip Enhanced Raman & Fluorescence
Metal AFM probe
Tip-enhanced Raman
~ λ / 2
Focused laser spot
(a)Electron charge density oscillations of a localized surface plasmon at the end of a sharp metal wire; corresponding distribution of the electromagnetic field (light) localized a few dozen nanometers around the tip apex.
(b)Experimental example of a TERS probe (etched metal wire)
Data from S. Kharintsev, A. Noskov, G. G. Hoffmann and J. Loos, Nanotechnology 22 (2011), 025202.
AFM - Raman - SNOM - TERS
NTEGRA Spectra
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