Change in the Infra-Red Absorption Spectrum of Water with Temperature

Abstract

By the use of two constant deviation spectrometers in series and a Coblentz linear thermopile, the absorption coefficient of water was measured for various temperatures from 0\ifmmode^\circ\else\textdegree\fi{} to 95\ifmmode^\circ\else\textdegree\fi{}C. The bands found showed maximum absorption at the following wave-lengths There is a shift toward shorter wave-lengths as the temperature increases and also a marked increase in magnitude of the maximum absorption for the bands at.77,.98 and $1.21\ensuremath{\mu}$. These changes are qualitatively explained by Roentgen's hypothesis that water is a mixture of at least two kinds of molecules, presumably ${({\mathrm{H}}_{2}\mathrm{O})}_{2}$ and ${({\mathrm{H}}_{2}\mathrm{O})}_{3}$, whose relative amounts change with a change of temperature.