Spectroscopy: IR: Normal modes of vibration of methyl CH3R


asymmetrical stretching νas(CH3) symmetrical stretching νs(CH3) asymmetrical bending δas(CH3)
Nu_as_1 Nu_as_2 Nu_s Delta_as_1 Delta_as_2

≈ 3000-2850 cm-1 (VS / VS)

≈ 3000-2850 cm-1 (MS / MS)

≈ 1470-1450 cm-1 (M / W)

symmetrical bending δs(CH3) rocking ρ(CH3) torsion τ(CH3)
Delta_s Rho1 Rho2 Tau

≈ 1395-1365 cm-1 (M / W)

≈ 975-835 cm-1

≈ 200 cm-1

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