Observation of the rotational spectrum of molecular hydrogen under stimulated Raman scattering conditions

An experimental investigation was made of simultaneous excitation of purely rotational S₀(1), S₀(3), and S₀(5) transitions in the orthohydrogen molecule (T = 300 K) under stimulated Raman scattering conditions. More accurate values were found of the coefficients in the expansion of the energy of the rotational terms of the H₂ molecule in powers of the rotational quantum number J of the ground vibrational state. The observed complex scattering spectrum was accounted for by biharmonic pumping in stimulated Raman scattering.