The Reflection Spectrum of Quartz in the Region of 9 mu

Abstract

The reflection spectrum of quartz, cut perpendicularly to the optic axis, has been previously studied in the region of 9μ. It was felt advisable to repeat this work by using polarized light and a crystal section cut parallel to the optic axis. With the same high resolution spectrometer and a new type of resonance radiometer which employs a Nichols type radiometer, sufficient sensitivity was obtained to bring out a maze of fine structure. It is to be noted that much of this fine structure is produced at identical frequencies for both the ordinary and the extraordinary rays. This might indicate that these frequencies are produced by a lattice rather than by an ionic motion, or that such agreement is entirely fortuitous because of the extreme complexity and closeness of the lines.