Development of a Curved Quartz Crystal X-Ray Spectrograph and a Determination of the Grating Constant of Quartz

Abstract

The construction of a small experimental spectrograph of the curved crystal type is described. The use of quartz instead of mica or gypsum which are customarily used and the improvement of the spectra obtained when quartz is used are discussed. The theory of the curved crystal x‐ray spectrograph has been extended in two ways: (1) to cover the doubling of spectral lines which arises due to reflections from opposite surfaces of the crystal, and (2) to cover the vertical separation of spectral lines produced by reflections from opposite sides of atomic reflecting planes. This latter effect is traced to a nonparallelism between the reflecting planes and the axis of curvature of the crystal. By means of the curved crystal spectrograph the grating constant for the basal planes of quartz was determined. This value was found to be $$\text{d=5.393±0.002}\mathrm{A}.$$