An Infra-Red Study of Several Liquid Crystals

Abstract
The near infra‐red spectra of three liquid crystals have been studied in the isotropic and anisotropic phases, and several band shifts have been observed. A detailed study of the transmission as a function of temperature was made at various wave‐lengths. Pronounced changes in transmission were observed at melting and clearing points, the magnitude of the changes being greater at short wave‐lengths. Rapid variations in transmission occurred in the mesophase. A qualitative explanation of the observed changes is given in terms of Ornstein's theory of scattering. The application of infra‐red methods to the study of changes of state is discussed.