“…The broad band ranging from 250 to 300 nm was attributed to the CTB, while the sharp peaks in the range of 300–500 nm arose from the f–f transitions of Eu 3+ . Specifically, the peaks located at 320, 361, 376, 382, 395, 416 and 465 nm corresponded to the 7 F 0 → 5 H 3 , 5 D 4 , 5 G J , 5 L 7 , 5 L 6 , 5 D 3 , and 5 D 2 transitions of Eu 3+ ions [ 5 , 51 , 52 , 53 ]. All the spectral lines in the SrMn x Eu host appeared to be wider when compared to those in other hosts that have been described.…”