Title: Seaborgium
CAS Registry Number: 54038-81-2
Additional Names: Element 106; unnilhexium
Literature References: Sg, Unh; at. no. 106. Group VIB (6). No stable nuclides. Prepn of isotope 263106 (a-emitter; T½ 0.9 ±0.2 sec; longest-lived known isotope; rel. at. mass 263.1186) by 249Cf (18O,4n): A. Ghiorso et al., Phys. Rev. Lett. 33, 1490 (1974). Four known isotopes: 259-261, 263. Confirmation of discovery: K. E. Gregorich et al., ibid. 72, 1423 (1994). Review of history, prepn and properties: 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 1108-1110; P. Armbruster, Proc. Int. Sch. Phys. "Enrico Fermi" 222-240 (1986); G. N. Flerov, G. M. Ter-Akopian, Prog. Particle Nucl. Phys. 19, 197-239 (1987); G. T. Seaborg, W. D. Loveland, The Elements Beyond Uranium (John Wiley & Sons, Inc., New York, 1990) p 54-56; Transfermium Working Group, Pure Appl. Chem. 65, 1757-1814 (1993). |