Theoretical and Experimental Investigation of the Tb<sup>3+</sup> → Eu<sup>3+</sup> Energy Transfer Mechanisms in Cubic A<sub>3</sub>Tb<sub>0.90</sub>Eu<sub>0.10</sub>(PO<sub>4</sub>)<sub>3</sub> (A = Sr, Ba) Materials
Journal of physical chemistry. C./Journal of physical chemistry. C