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Electric dipole Transition moment. Elastic and Inelastic Scattering Raman. Powerpoint Templates. Rayleigh Scattering vs Raman Scattering. Interaction between electric field of incident photon and molecule Electric field oscillating with incident frequency v i :
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Elastic and Inelastic Scattering Raman Powerpoint Templates
Rayleigh Scattering vs Raman Scattering
Interaction between electric field of incident photon and molecule Electric field oscillating with incident frequency vi: Induces molecular electric dipole (p): Proportional to molecular polarizability, Polarization results in nuclear displacement Classical Raman Physics
For small distortions, polarizability is linearly proportional to the displacement • Resultant dipole: Rayleigh Scattering Stokes Raman Anti-Stokes Raman
Roto-Vibrational Raman ΔJ = 0 ± 2 LineSpacing 4B
Ressonance Raman Scattering effect enhanced by a factor 106
Lasers Ar+ ion 488.0 nm & 514.5 nm • Kr+ ion 530.9 nm & 647.1 nm • He:Ne 632.8 nm • Nd:YAG 1064 nm • Diode 630 nm & 980 nm • Resolution < 6 cm-1 → • Laser Linewidth < 1 cm-1 • Wavelength Stabilization is a must have • (most common 785 nm NIR 300mW