Mendelevium is a synthetic element with the symbol "Md" (formerly Mv) and the atomic number 101. A metallic radioactive transuranic element in the actinide series, mendelevium is usually synthesized by bombarding einsteinium with alpha particles. It was named after Dmitri Ivanovich Mendeleev, who created the Periodic Table. Mendeleev's periodic system is the fundamental way to classify all the chemical elements. The name "mendelevium" was accepted by the International Union of Pure and Applied Chemistry (IUPAC). On the other hand, the proposed symbol "Mv" submitted by the discoverers was not accepted, and the IUPAC selected "Md" instead. The radioactivity of the trivalent element, mendelevium, is definitely noteworthy. It was expected that the reaction would be253Es (α,n) 255Md, where 255Md was α-active with a t½ of 5 minutes and the corresponding α-energy. No such α-activity was observed, but the 101 fraction showed spontaneous fission representing a t½ less than 3 hours. Mendelevium (for Dimitri Ivanovich Mendeleev, surname commonly transliterated into Latin script as Mendeleev, Mendeleyev, Mendeléef, or even Mendelejeff, and first name sometimes transliterated as Dmitry or Dmitriy) was first synthesized by Albert Ghiorso, Glenn T. Seaborg, Gregory R. Choppin, Bernard G. Harvey, and Stanley G. Thompson (team leader) in early 1955 at the University of California, Berkeley. The team produced 256Md (half-life of 87 minutes) when they bombarded an 253Es target with alpha particles (helium nuclei) in the Berkeley Radiation Laboratory's 60-inch cyclotron (256Md was the first isotope of any element to be synthesized one atom at a time).Element 101 was the ninth transuranic element synthesized. The first 17 atoms of this element were created and analyzed using the ion-exchange adsorption- elution method. During the process, mendelevium behaved very much like thulium, its naturally occurring homologue. Sixteen isotopes of mendelevium from mass 245 to 260 have been characterized, with the most stable being 258Md with a half-life of 51.5 days, 260Md with a half-life of 31.8 days, and 257Md with a half-life of 5.52 hours. References: ^ Hall, Nina (2000). The new chemistry. Cambridge University Press. pp. 9– 11. ISBN 0521452244. ^ Johansson, Börje; Rosengren, Anders (1975). "Generalized phase diagram for the rare-earth elements: Calculations and correlations of bulk properties". Physical Review B 11: 2836. Bibcode 1975PhRvB..11.2836J. doi:10.1103/PhysRevB.11.2836. ^ Ghiorso, A.; Harvey, B.; Choppin, G.; Thompson, S.; Seaborg, G. (1955). "New Element Mendelevium, Atomic Number 101". Physical Review 98: 1518. Bibcode 1955PhRv...98.1518G. doi:10.1103/PhysRev.98.1518. ^ Hofmann, Sigurd (2002). On beyond uranium: journey to the end of the periodic table. CRC Press&year=2002. pp. 40–42. ISBN 0415284961. ^ Audi, G (1997). "The N? evaluation of nuclear and decay properties". Nuclear Physics A 624: 1. Bibcode 1997NuPhA.624....1A. doi:10.1016/S0375-9474(97)00482-X. ^ Lide, D. R., ed (2005). CRC Handbook of Chemistry and Physics (86th ed.). Boca Raton (FL): CRC Press. ISBN 0-8493-0486-5.