Measurements of the Absorption of Light in Low-Loss Liquids

Measurements have been made of the absorptivity of 31 low-loss liquids by a new technique. The change of refractive index of the sample caused by the temperature change due to absorption of light was measured with an interferometer. Absorptivity values as small as 10−5 cm−1 have been measured. The lowest values were obtained for carbon tetrachloride, chloroform, and bromobenzene. The absorptivity of heavy water is <5×10−5 cm−1, 1/60 that of ordinary water at the same wavelength. Measurements were made at 6328 Å.