Investigation of stimulated Raman scattering of ν1 and ν2 modes in CH4

Using 355 nm excitation laser radiation, the stimulated Raman scattering (SRS) lines of methane between 14 000 and 26 000 cm−1 at different experimental conditions were recorded. Two sets of successive SRS lines manifesting the Raman shift in the ν1 and ν2 modes of vibration in the 1A1 electronic state of CH4 have been assigned. The evolution of SRS lines at different pressures has been investigated. The energy dependence of SRS lines has revealed that SRS line due to higher order components become stronger than the fundamental at higher laser pump energy.