Evidence for the formation of sodium hassate(VIII)

Abstract

Summary Hassium, element 108, was produced in the fusion reaction between 26 Mg and 248 Cm. The hassium recoils were oxidized in-situ to a highly volatile oxide, presumably HsO 4 , and were transported in a mixture of He and O 2 to a deposition and detection system. The latter consisted of 16 silicon PIN-photodiodes facing a layer of NaOH, which served, in the presence of a certain partial pressure of water in the transport gas, as reactive surface for the deposition of the volatile tetroxides. Six correlated α-decay chains of Hs were detected in the first 5 detectors centred around detection position 3. In analogy to OsO 4 , which forms Na 2 [OsO 4 (OH) 2 ], an osmate(VIII), with aqueous NaOH, HsO 4 presumably was deposited as Na 2 [HsO 4 (OH) 2 ], a hassate(VIII).