Site and local structure of activator Eu2+ in phosphor Ca10−x(PO4)6Cl2:xEu2+

The d→f emission of Eu2+ in Ca9.9(PO4)6Cl2:0.1Eu2+ can be assigned as: emission profile at 2.71 eV and 2.61 eV are Eu2+ at 6h and 4f site, respectively.