Question

Calculate the wavelength ranges to be scanned for CHCl3 and CCl4 for the (a) Stokes spectra and (b) anti-Stokes spectrum assuming that the wavelength of the laser is 532.2 nm and that the range of vibrational frequencies is 100-3200 cm^-1 for CHCl3 and 100-1000 cm^-1 for CCl4

Answer 1

wavenumber (cm^-1 ) = 1/wavelength (nm)

wavelength of the laser = 532.2nm which corresponds to 532.2 x 10^-7 cm

wavenumber = 1/ (532.2 x 10^-7) = 1.87 x 10⁴ cm^-1

Peaks range for CHCl3 will be 100 -3200 cm^-1

stroke line = (1.87 x 10⁴ ) - 100 = 1.86 x 10⁴ = 535.05 nm.................................. for 100 cm^-1

= (1.87 x 10⁴) - 3200 = 1.53x 10⁴ = 653.59 nm .................................. for 3200 cm^-1

antisroke = (1.87 x 10⁴ ) + 100 = 1.88x x 10⁴ = 532nm.................................. for 100 cm^-1

=(1.87 x 10⁴) + 3200 = 2.19 x 10⁴ = 457 nm .................................. for 3200 cm^-1

For CCl4

stroke = (1.87 x 10⁴) -1000 = 1.77 x 10⁴ = 565 nm .................................. for 1000 cm^-1

antistroke = (1.87 x 10⁴) +1000 = 1.97 x 10⁴ = 508 nm .................................. for 1000 cm^-1