On the Infrared Absorption of Water and Heavy Water in Condensed States

The infrared spectra (from 2 to 30 μ) of thin films of H 2 O and D 2 O were measured at various temperatures between 20 ° and −180 °C. A strong absorption band due to the librational mode of the water molecule has its maximum around 710 cm. −1 in the liquid. In ice it is shifted to 800 cm. −1 at −15 °C. and 850 cm. −1 at −170 °C. The corresponding D 2 O bands show the normal isotope shift. Thin films of water pressed between silver chloride plates could not be crystallized even at liquid air temperature as confirmed by their spectra, which were almost identical with those of the liquid.