Electron-Diffraction Study of the Structure of Supercooled Liquid Bismuth

Abstract

Thin bismuth films were prepared on crystal surfaces by evaporation And the liquid state of the films at temperatures above and below the ordinary melting point (271°C) has been studied by means of the reflexion method of electron diffraction. The marked supercooling of the films (M. Takagi: J. Phys. Soc. Japan 9 (1954) 359) has been utilized for the study below the melting point. A method to eliminate difficulties inherent to the intensity measurement by reflexion method and a method to refine the observed intensity values were developed. The radial distribution curves at 400°C, 271°C (the melting point), 175°C, 130°C and 110°C (a little above the solidification temperature) were computed from experimental data. The curves showed a systematic change with temperature. It was revealed that the atomic arrangement at 110°C resembles closely that of solid bismuth. Above the melting point a tendency towards close-packed structure was noted.