Growth and luminescent properties of new Eu $^{2+}$ doped RbBa$_{2}$I$_{5}$ scintillator

A novel crystal scintillator of RbBa$_{2}$I$_{5}$:Eu$^{2+}$ was grown by the Bridgman–Stockbarger method. Its luminescence and scintillation properties were investigated. Under X-ray excitation, the crystal demonstrates blue luminescence peaking at 436 nm associated with 4f$^{6}$5d$^{1}$ → 4f$^{7}$ radiative transitions of Eu$^{2+}$ ions. The main X-ray luminescence decay constant is 800 ns. The light output of RbBa$_{2}$I$_{5}$:3%Eu$^{2+}$ sample under 662 keV excitation is 58,200 ph/MeV.