Van deusen

• B-C-P
• Ba-Ca-Cu-O-Tl
• Ba-Ca-Cu-O-Pb-Sr-Tl
• electronic and electrical properties
• permittivity (dielectric constant)
• optical properties
• optical conductivity
• phonons
• conductor
• ternary
• semiconductor
• metalloid
• pnictogen
• trigonal
• tetragonal