Infra-Red Absorption Spectra of the Water Molecule in Crystals

The paper reports the absorption spectra taken under high resolution and dispersion near $3\mu$ which are produced by water in various bound states in certain crystals and indicates the modes of vibration which cause the observed bands. Bands in sodium bromide, NaBr·2${\mathrm{H}}_2$O, extending from 3 to $2\mu$, and bands near $2.5\mu$ in sodium iodide, NaI·2${\mathrm{H}}_2$O, and barium chloride, Ba${\mathrm{Cl}}_2$·2${\mathrm{H}}_2$O, are reported and discussed. The absorption of beryl, mica, topaz, and quartz from 2 to $3\mu$ is also studied. It is concluded that bands in beryl, which are strikingly similar to bands of water dissolved in carbon tetrachloride, are caused by monomeric water, or vapor-like molecules, in solid solution in the open crystal lattice of beryl. In mica, it is concluded, only bound hydroxyl groups are present. The evidence indicates that both bound hydroxyl groups and highly perturbed coordinated water exist in topaz. In fused quartz there is evidence for the existence, in some samples, of water in solid solution.