Tl₂ZrCl₆ crystal: Efficient scintillator for X- and γ-ray spectroscopies

Crystal growth and luminescence properties of the intrinsic Tl₂ZrCl₆ scintillation crystal are presented. The proposed crystal is a promising candidate for γ-ray detection owing to its high light yield, good energy resolution, and high effective atomic number (Z = 69). It has a cubic structure, which is desirable for a large-size-crystal growth. In this study, the crystal is grown from its melt using the Bridgman technique. The emission peak under X-ray excitation is found at 460 nm, with a primary decay time of 2.7 μs. The light yield and energy resolution are estimated to be 47,000 photons/MeV and 4.3% (full-width-at-half-maximum), respectively, obtained from the pulse-height spectra under a ¹³⁷Cs 662-keV γ-ray excitation.