Used in specialized optical applications, particularly in infrared (IR) spectroscopy, due to its transparency in the IR range. It serves as a component in the synthesis of other rubidium compounds and in certain types of chemical research where a soluble iodide source is needed. Also explored in some solid-state and electronic materials research, including in the development of scintillation detectors for radiation measurement. Occasionally used in experimental physics and chemistry involving alkali metal halides.