Scintillation characterizations of Rb₂LiGdCl₆: Ce³⁺ single crystals

In the present work, we reported on the scintillation characterizations of our newly developed cerium doped Rb₂LiGdCl₆ (RLGC) single crystal. RLGC belongs to elpasolite family and is grown by vertical Bridgman technique with 0% and 1% Ce³⁺ contents (mole %). Under X-ray excitation, two overlapped emission peaks are obtained between 350 to 450 nm wavelengths for 1% Ce sample. Such emission is attributed to cerium ion present in the crystal matrix. At 662 keV γ-rays RLGC: 1% Ce³⁺ crystal showed energy resolution and light yield of 8.1% (FWHM) and ∼ 13,000 ph/MeV, respectively at room temperature. Under γ-ray excitation, RLGC: 1% Ce³⁺ crystal showed three exponential decay time components. Further improvement in the scintillation properties is expected with higher values of Ce- concentrations. A major drawback of this material is the presence of ⁸⁷Rb radioisotope and its highly hygroscopic nature. However, the presence of Li and Gd ions in the matrix make this material suitable candidate for the use of thermal neutron detection.