Chalcogen, Metal, Electronic and electrical properties, Trigonal

• Bi-Fe-O
• La-Mn-O-Sr
• Ca-Cu-O-Ti
• Bi-Te
• Bi-Se
• conductivity or resistivity
• electrical resistivity
• permittivity (dielectric constant)
• metal or nonmetal character
• temperature for metal-nonmetal transition
• metal
• chalcogen
• conductor
• transitional
• disordered