Meitnerium

Meitnerium is a synthetic, radioactive element with atomic number 109, positioned in group 9 below iridium. Its production in extremely small quantities and the short lifetimes of its known isotopes make experimental investigation difficult. Chemical behavior is largely predicted from its position in the periodic table and theoretical calculations, while bulk physical properties remain experimentally unestablished. Meitnerium has no established commercial applications and is studied as part of research on superheavy nuclei and the limits of the periodic table.