Mendelevium (element 101)

Characteristics

As a member of the actinide group the element is expected to show metallic behavior, though bulk physical properties are poorly known. It is radioactive, decays by alpha emission or electron capture depending on the isotope, and has no stable isotopes. Early literature referred to the element by the symbol Mv; that symbol has since been replaced by Md.

Production and isotopes

Mendelevium is produced artificially by nuclear reactions. The original synthesis was achieved by bombarding einsteinium with alpha particles — helium nuclei — causing the nuclei to fuse and form atoms of mendelevium. Laboratories today typically make the element in very small quantities using particle accelerators or specialized reactors; these methods yield a range of short-lived isotopes used for experimental study. The target material for its first synthesis was the element einsteinium.

Discovery and name

Mendelevium was first identified in the mid-20th century by a team of researchers working with transuranic elements. The element was named in honor of the Russian chemist Dmitri Mendeleev, the developer of the periodic classification that predicted properties of many elements. Its placement as element 101 reflects the sequence of artificially produced heavy elements added to the periodic table.

Uses, handling, and significance

• Uses: restricted to scientific research into nuclear reactions and the chemistry of heavy actinides.
• Safety: like other heavy radioactive elements, it requires strict radiological controls and is handled only in specialized facilities.
• Importance: studies of mendelevium contribute to understanding electronic structure, bonding, and nuclear behavior in the heaviest elements.

Because of its scarcity and radioactivity, mendelevium remains of interest primarily to nuclear chemists and physicists exploring the properties of the heaviest members of the periodic table. For more technical summaries and data, see introductory resources on heavy element synthesis and actinide chemistry (metallic properties).