Behaviour of the Eu3+5D0 → 7F0 transition in CaMoO4 powellite type ceramics under Ar and Pb ions implantation

Abstract In this work, the Eu 3+ 5 D 0  →  7 F 0 transition is used as a structural probe to follow the Eu 3+ environment modification in powellite CaMoO 4 under irradiation or when its composition is varying. Six ceramics with compositions ranging from Ca 0.99 Eu 0.01 MoO 4 to Ca 0.76 Sr 0.1 Na 0.07 Eu 0.01 La 0.02 Nd 0.02 Pr 0.02 MoO 4 were synthesized and each composition has a specific Eu 3+ luminescence signal. The 5 D 0  →  7 F 0 transition appeared to be a very sensitive structural probe. Even if there is only one structural site in powellite for europium, the Eu 3+ 5 D 0 level position changes with the modification of the Eu 3+ cationic neighbours. Low 5 D 0 values are observed for environments containing trivalent rare earth elements when high 5 D 0 values are observed for Na + rich environments. Under 8 MeV Ar ions irradiation, the Eu 3+ 5 D 0  →  7 F 0 transition is not really affected. Under 108 MeV Pb ions irradiation there is an homogenization of the Eu 3+ 5 D 0  →  7 F 0 transition from the different irradiated samples revealing a reorganization of the crystalline structure.