Alkali, Cell and atoms, Chalcogen, Electronic energy gap, Trigonal

• Mo-Rb-Se
• Mo-Rb-S
• H-K-Ni-O
• Co-Na-O
• Au-Rb-Se
• values of electronic energy gap
• energy gap for direct transition
• energy gap for indirect transition
• chalcogen
• alkali
• transitional
• disordered