Experimental investigations of transactinoide elements provide benchmark results for chemical theory and probe the predictive power of trends in the periodic table. So far, in gas-phase chemical reactions, simple inorganic compounds with the transactinoide in its highest oxidation state have been synthesized. Single-atom production rates, short half-lives, and harsh experimental conditions limited the number of experimentally accessible compounds. We applied a gas-phase carbonylation technique previously tested on short-lived molybdenum (Mo) and tungsten (W) isotopes to the preparation of a carbonyl complex of seaborgium, the 106th element. The volatile seaborgium complex showed the same volatility and reactivity with a silicon dioxide surface as those of the hexacarbonyl complexes of the lighter homologs Mo and W. Comparison of the product's adsorption enthalpy with theoretical predictions and data for the lighter congeners supported a Sg(CO)6 formulation.

Chemical studies of superheavy elements require fast and efficient techniques, due to short half-lives and low production rates of the investigated nuclides. Here, we advocate for using a tubular flow reactor for assessing the thermal stability of the Sg carbonyl complexSg(CO) 6 . The experimental setup was tested with Mo and W carbonyl complexes, as their properties are established and supported by theoretical predictions. The suggested approach proved to be effective in discriminating between the thermal stabilities of Mo(CO) 6 and W(CO) 6 . Therefore, an experimental verification of the predicted Sg−CO bond dissociation energy seems to be feasible by apply- Tc carbonyl complex, we estimated the lower reaction time limit for the metal carbonyl synthesis in the gas phase to be more than 100 ms. We examined further the influence of the wall material of the recoil chamber, the carrier gas composition, the gas flow rate, and the pressure on the production yield of 104 Mo(CO) 6 , so that the future stability tests with Sg(CO) 6 can be optimized accordingly.

The projectile fragmentation reactions of 40 Ar at 57 MeV/nucleon on 9 Be and 181 Ta targets have been studied by the Radioactive Ion Beam Line in Lanzhou (RIBLL) at the Heavy-Ion Research Facility in Lanzhou (HIRFL). The momentum distributions of fragments have been measured and the competition between different mechanisms are observed. The production cross sections have been obtained and compared with the empirical parametrization of fragmentation cross section (EPAX), abrasion-ablation (AA), and heavy-ion phase space exploration (HIPSE) models, and the target dependence of fragment cross sections has also been discussed.

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This paper reports the measurement of the energy loss of protons at the energy of 100 keV penetrating a partially ionized hydrogen plasma. The plasma of ne ≈ 1015–16 cm−3; Te ≈ 1–2 eV and lifetime of about 8 µs is created by the hydrogen gas discharge. The experimental results show an increase of a factor of 2.8 in the energy loss, which are in good agreement with the Bethe, Standard Stopping Model, Li–Petrasso and Vlasov models’ predictions within the error limit. The Bethe–Bloch Coulomb logarithm term is found to increase by a factor of 4.0 for free electrons as compared with the situation where bound electrons prevail. The potential application of protons energy loss for diagnosing the electron density in plasma is proposed too.

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