A method of material design for systematic absence of X-ray diffraction

Materials with systematic absence of X-ray diffraction (XRD) peaks are desirable for conducting some special researches using X-ray diffraction or time-resolved X-ray scattering. This paper proposes a method for designing this kind of materials. It utilizes solid solution to reduce the structure factor of a selected reflection to zero by choosing proper components and their contents to let the reflection amplitudes from different atomic layers in a unit cell of the solid solution cancel each other completely. This method on how to select a solid solvent and how to calculate its content was illustrated using SrTiO3 as an example. A solid solution Sr1−xCaxTiO3 with a systematic absence of the (001) diffraction can be designed, and the value of x can be determined to be x=0.54 using an iteration calculation process. This result was verified by the experimental XRD pattern of a Sr0.46Ca0.54TiO3 sample.