X-ray excited ultralong room-temperature phosphorescence for organic afterglow scintillators

We present X-ray-excitable organic ultralong room temperature phosphorescence (X-OURTP) for afterglow scintillators through implanting lone-pair electron involved n-π∗ transitions and efficient charge transfer characters into H-aggregations of organic crystals. The thus designed X-OURTP molecule exhibits ultralong lifetimes up to 790 ms, high phosphorescence quantum yields of ∼8%, and excellent scintillation stability. These findings will pave the way to the design of organic afterglow scintillators, simulating extensive investigations on the extraordinary X-OURTP.