Eu3+ luminescence in high-symmetry sites of natural apatite

A molecular receptor targeted, hydroxyapatite nanocrystal based multi-modal contrast agent

“…Most importantly, it can be seen that, at 2% and 3% Eu 3þ , intensity of the NIR peak at 700 nm was found to be much more efficient than the other two typical emissions at 590 and 616 nm. This is a significant change, which was generally not observed in the earlier reports related to Eu 3þ doped apatite crystals [37,38].…”

“…Both these emission centers are known to produce red emissions at 616 nm and 595 nm due to the hypersensitive electric-dipole transitions at 5 D 0 / 7 F 2 , and 5 D 0 / 7 F 1 , respectively [38]. However, the significantly enhanced NIR emission observed in the present case, due to 5 D 0 / 7 F 4 transition, was not found efficient in calcium apatite crystals doped with Eu 3þ at both Ca 2þ (I) and Ca 2þ (II) sites.…”

Diffusion under irradiation of rare earth elements in apatite

“…positions (578, 591 and 617 nm) [9]. In figure 3 we observe that after bombardment, the first set related to CaCm substitution disappears while the second one related to Ca(l) substitution remains.…”

“…Europium is representative of actinides as the chemical properties of Eu 3 + are very similar to those of trivalent actinides and more precisely to Am3+. Furthermore, Eu 3 + can be used as a local structural probe [9]. Implantation is used to introduce La and Eu ions into apatite.…”

Luminescence properties of Eu2+ and Eu3+ doped calcium-deficient hydroxyapatite prepared in air

“…The distance is retained when the Ca 2+ ion is substituted by Eu 3+ and the intensity of the charge transfer band (CT band) should be higher [23]. As shown in Fig.…”