Depolarized Rayleigh scattering study of neat formamide

The depolarized Rayleigh spectrum of formamide has been measured as a function of temperature. The spectrum of neat formamide indicates that the static orientation pair correlation factor, g₂, is large compared to other small molecular fluids. The experimental slope of τ_Ray plotted vs. η_s/Τ is found to be close to the theoretical slope obtained by assuming slip boundary conditions. Within the experimental error a nonzero intercept is also found. The depolarized Rayleigh spectrum may also reflect translation-rotation coupling if the reorientational motion couples to the shear wave. The shear wave dip in the Lorentzian peak is not wide enough to be resolved in neat formamide.