From Current Literature

Production of Amorphous Water

Attempts to obtain water in a glass-like state by rapidly cooling the liquid phase have so far been unsuccessful, apparently owing to the high rate of formation of crystallization centers and of growth of ice crystals.

Luyet, in his report[^1], states that he has for the first time observed “solid” water. After a number of unsuccessful attempts at cooling in liquid air small aqueous droplets, he used the following method.

A jet of water fell between two parallel, vertically arranged copper disks; one of them was mounted fixed, the other attached to a spring. Before the experiment began, both disks were cooled in liquid air. Then one of them, by a push of the spring, struck the other; the jet broke up and formed between the disks the thinnest film, a few microns thick. Pieces of this film were transferred to a special dried chamber and examined in a polarization microscope. For approximately the first 30 sec. the field of view with crossed nicols remained dark. Then, as the temperature in the chamber gradually increased, and at temperatures close to the melting point of ice, one could observe under the microscope the filling of the film with crystals. The author concludes that the water was initially obtained in an amorphous state. He notes, however, that there remains the possibility, not excluded, of crystallization centers of dimensions smaller than the wavelength of the light incident into the microscope having formed in the film from the very beginning.

E. Kofman, Moscow

Literature

1. B. Luyet, Phys. Rev., 56, 1244, 1939.