Stimulated Raman scattering investigation of isotopic substitution H2O/D2O system

Abstract

Stimulated Raman scattering（SRS）was used to study H2O, D2O, and their mixtures with different volume ratios. The peaks of the ice-like tetrahedral hydrogen bond structure and the peaks associated with the interaction between OH/OD groups and excess electrons in the hydrated electron clusters were observed in the forward SRS spectra. Due to the influence of isotopic substitution, the hydrogen bond structure is transformed from ordered to disordered and the binding of OH groups to electrons is weakened, the Raman peaks move toward high wavenumbers and new peaks arise. Influenced by the SRS excitation mechanism, the SRS peaks of the isotopic substitution H2O/D2O system show dependence on the substitution ratio, and the vibration mode of a single stretching region can be selected for excitation. Furthermore, the hydrogen bond structure differences in H2O and D2O are further discussed.