Mendelevium

Literature References: Md; formerly Mv; at. no. 101; valence 3, 2. Man-made radioactive element. No stable nuclides; known isotopes (mass numbers): 247-252, 254-259. Longest-lived known isotope 258 (T½ 55 days, a-emitter, rel. at. mass 258.0984). Prepn of isotope 256Md (T½ 1.27 hrs, rel. at. mass 256.0941; decays by electron capture to 256Fm) by bombarding 253Es with helium ions: A. Ghiorso et al., Phys. Rev. 98, 1518 (1955). Prepn of isotope 258Md by bombardment of 255Es with 4He ions: Fields et al., Nucl. Phys. A 154, 407 (1970). Reviews: C. Keller, The Chemistry of the Transuranium Elements (Verlag Chemie, Weinheim, English Ed., 1971) pp 595-600; Silva, "Trans-Curium Elements" in MTP Int. Rev. Sci.: Inorg. Chem., Ser. One vol. 8, A. G. Maddock, Ed. (University Park Press, Baltimore, 1972) pp 71-105; Comprehensive Inorganic Chemistry vol. 5, J. C. Bailar, Jr. et al., Eds. (Pergamon Press, Oxford, 1973) passim; Handb. Exp. Pharmakol. 36, 689-738 (1973); R. J. Silva in The Chemistry of the Actinide Elements vol. 2, J. J. Katz et al., Eds. (Chapman and Hall, New York, 1986) pp 1092-1095; The Elements Beyond Uranium, G. T. Seaborg, W. D. Loveland, Eds. (John Wiley & Sons, Inc., New York, 1990) p 38-46.