Chalcogen, Nonmetal, Rare earth, Energy level diagram, Tetragonal

• Er-O-V-Y-Yb
• Ca-Eu-O-W
• Er-Gd-O-V-Yb
• Er-Eu-Mg-O-Si-Sr
• Bi-O-V-Y
• chalcogen
• nonmetal
• rare earth
• luminescent
• lanthanoid