Knowledge Bank

Infrared spectra from $4000cm-1$ to $32cm-1$ of $SF6$ have been recorded at several pressures, from below atmospheric pressure up to 20 atmospheres and in the liquid from $-40\circ$ C to $10\circ$ C. Their active fundamentals, the difference bands, the combination and the harmonic bands, and the collision induced band in the f-ir were observed. Integrated intensities were measured at several densities. When the sample is liquefied, the bands involving $v3$, a except the fundamental itself, are split into two components. No collision induced band was observed in the m-ir.