The sorption of tetravalent plutonium onto kaolinite, a clay mineral, has been studied as a function of pH. The sorption studies have been performed by batch experiments under aerobic and anaerobic conditions (glove box). A pH range of 0–11 has been investigated with plutonium concentrations of 3.5 × 10

Adsorption / Transactinides / Element 112 / ThermochromatographySummary. Two experiments aiming at the chemical investigation of element 112 produced in the heavy ion induced nuclear fusion reaction of 48 Ca with 238 U were performed at the Gesellschaft für Schwerionenforschung (GSI), Darmstadt, Germany. Both experiments were designed to determine the adsorption enthalpy of element 112 on a gold surface using a thermochromatography setup. The temperature range covered in the thermochromatography experiments allowed the adsorption of Hg at about 35 • C and of Rn at about −180 • C. Reports from the Flerov Laboratory for Nuclear Reactions (FLNR), Dubna, Russia claim production of a 5-min spontaneous fission (SF) activity assigned to 283 112 for the 238 U( 48 Ca,3n) 283 112 reaction. Hence, Experiment I was designed to detect spontaneously fissioning (SF) isotopes of element 112 with half-lives (t 1/2 ) longer than about 20 s. 11 high-energy events were detected. 7 events exhibit a deposition pattern resembling a chromatographic peak in the vicinity of Rn deposition. However, the energy of the events observed in Experiment I was lower than expected for a SF-decay of 283 112. Therefore, these events could not be unambiguously attributed to the decay of 283 112. In contradiction with earlier publications newer reports from FLNR Dubna claim that 283 112 decays by α-particle emission (E α = 9.5 MeV) with t 1/2 = 4 s followed by a SF-decay of 279 Ds (t 1/2 = 0.2 s). Therefore, Experiment II was designed to be sensitive to both claimed decay properties of 283 112. However, during

Element 108 / Hassium / Volatile HsO 4 / In-situ production / Adsorption on hydroxide / CALLISTO 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).

We report on a formulation and implementation of a scheme to compute nuclear magnetic resonance (NMR) shieldings at second-order Møller–Plesset (MP2) perturbation theory using gauge-including atomic orbitals (GIAOs) to ensure gauge-origin independence and Cholesky decomposition (CD) to handle unperturbed and perturbed two-electron integrals. We investigate the accuracy of the CD for the derivatives of the two-electron integrals with respect to an external magnetic field and for the computed NMR shieldings, before we illustrate the applicability of our CD-based GIAO-MP2 scheme in calculations involving up to about 100 atoms and more than 1000 basis functions.

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