Trichloroterbium is primarily used in research and development within inorganic and materials chemistry. It serves as a precursor for synthesizing various terbium-containing compounds, especially in the preparation of luminescent materials. Due to terbium’s strong green emission under UV excitation, derivatives made from trichloroterbium are explored in the development of phosphors for lighting and display technologies, including LEDs and cathode-ray tubes. It is also employed in the creation of specialty glasses and optical coatings that require rare earth elements for enhanced performance. In addition, trichloroterbium finds use in catalytic studies involving rare earth metal centers and in the doping of crystals for solid-state lasers and other photonic devices. Its role as a building block in coordination chemistry enables the design of metal-organic frameworks (MOFs) with potential applications in sensing and magnetic materials.