Inelastic scattering of light

Inelastic scattering of light due to the excitation of vibrations had already been predicted in 1923 [37] and was confirmed experimentally a few years later by Raman [38], Because at that time the Raman effect was much easier to measure than infrared absorption, Raman spectroscopy dominated the field of molecular structure determination until commercial infrared spectrometers became available in the 1940s [10]. 

Raman spectroscopy is the inelastic scattering of light by the molecular vibrations of the sample (Figure 9-4A). It is similar to infrared (IR) spectroscopy in... 

Spectroscopic phenomenon Absorption of light hvm. = AFvibr Inelastic scattering of light hVQx hVsQ = A vibr... 

Brillouin scattering is the inelastic scattering of light by thermal acoustical phonons in a material. Energy and wavevector conservation in the process are given, respectively, by... 

Spectroscopic phenomenon Absorption of light hviR = ATiyibr Inelastic scattering of light hVex hVsc = A vlbr... 

Raman effect - The inelastic scattering of light by a molecule, in which the incident photon either gives up to, or receives energy from, one of the internal vibrational modes of the molecule. The scattered light thus has either a lower frequency (Stokes radiation) or higher frequency (anti-Stokes radiation) than the incident light. These shifts provide a measure of the normal vibrational frequencies of the molecule. 

Surface-enhanced Raman spectroscopy (SERS) is based on the amplification of the Raman effect - the inelastic scattering of light at molecules - at nanostructured metal surfaces. If light is scattered at molecules, a dipole moment H is induced to the molecule by an incident electromagnetic field E as described in Eq. 1. Here, oc represents the polarizability of the molecule - a measure to what extent the electric field E is able to disturb the electron density of a molecule out of its equilibrium configuration ... 

The scaling law for the inelastic scattering of light at a fixed wave vector q [eq. (VI.37)] is (within the Kiikwood approximation)... 

Several methods have been developed to evaluate the Leslie viscosity coefficients described in detail in [18, 28, 31]. These methods include the inelastic scattering of light [60, 93], pulse [94], and rotating [95] magnetic fields, attenuation of the ultrasound shear wave [96], etc. The results obtained by different methods for such important coefficients as rotational viscosity agree fairly well with each other [78], Fig. 2.25. The simplest and most useful methods for measuring 71-values are based on the dynamics... 

Raman spectroscopy is based on the inelastic scattering of light. Similar to IR spectroscopy the Raman technique yields information about vibrational modes of molecular bonds. A Raman spectrum can yield complementary information about the vibration modes observed in IR spectroscopy. However, Raman spectroscopy is not directly equivalent to IR spectroscopy. The condition for a molecular bond to be Raman active is a change in the polarization of the electron cloud during the interaction with a photon. 

Numerous methods are used to measure the mechanical properties of CNT observation of the deflection of a bundle of NTC by TEM [44, 45] or AFM [46, 47], tensile test between two AFM tips, and inelastic scattering of light [48], among others. 

Many spectroscopic methods based on the Raman effect, the inelastic scattering of light by molecules, have been developed and employed in various biophysical and bioanalytical applications (1-4). The value inherent in all of these methods lies in the rich information content of Raman spectra due to the dependences of molecular vibrational modes on the chemical and physical microenvironment of the analytes. However, exploiting this information content can be quite challenging due to fiindamental limitations in the sensitivity of the technique and/or practical limitations in the available experimental systems. Much effort has therefore focused on the development of instrumental configurations that endeavor to optimize the utility of the technique for a given application or class of applications. 

Raman spectroscopy involves inelastic scattering of light instead of absorption or emission. The selection mles for Raman transitions are different from those of absorption and emission spectroscopy, so that many transitions that are forbidden in absorption and emission occur in Raman scattering. Raman scattering requires that the motion modulate the polarizability of the molecule. For rotational Raman transitions in diatomic and linear polyatomic molecules... 

Raman spectroscopy is a vibrational optical spectroscopic technique based on the inelastic scattering of light by matter like the molecule of interest. Raman spectroscopy is a highly specific technique due to specific molecular fingerprint information as observed in the Raman spectra. This phenomenon was theoretically predicted by Smekal in 1923 (Smekal 1923). In 1928, the first experimental observation of RS effect was reported by Indian physicists C.V. Raman and K.S. Krishnan (Raman and Krishnan 1928a, b) and independently by Mandelstam and... 

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