A Nonlinear Optical Experiment: Stimulated Raman Scattering in Benzene and Deuterated Benzene

A nonlinear optical experiment is presented that utilizes a doubled Nd:YAG laser to produce stimulated Raman scattering (SRS) in benzene and deuterated benzene. A sampling arrangement is described that results in strong stimulated Raman emission involving symmetric CC and CH(CD) stretching modes in both C₆H₆ and C₆D₆. The wavelengths of the coherent beams are easily measured with a simple transmission grating and meter stick. Observations of both collinear and conical stimulated Raman beams are made and the reasons for these discussed. The measured frequencies permit calculation of CC and CH force constants in benzene.