Energy level diagram, Luminescent, Nonmetal, Rare earth

• Er-O-Ti
• Al-Ce-O-Y
• Ba-Ce-Cl-Eu-O-P
• Al-Ce-O-Y-Yb
• Al-La-O-Sr-Ta-Yb
• rare earth
• lanthanoid
• luminescent
• nonmetal
• chalcogen
• tetragonal
• cubic
• hexagonal
• trigonal
• orthorhombic