0000000000042602
AUTHOR
Kosuke Morita
Synthesis and detection of a seaborgium carbonyl complex
A carbonyl compound that tips the scales Life is short for the heaviest elements. They emerge from high-energy nuclear collisions with scant time for detection before they break up into lighter atoms. Even et al. report that even a few seconds is long enough for carbon to bond to the 106th element, seaborgium (see the Perspective by Loveland). The authors used a custom apparatus to direct the freshly made atoms out of the hot collision environment and through a stream of carbon monoxide and helium. They compared the detected products with theoretical modeling results and conclude that hexacarbonyl Sg(CO) 6 was the most likely structural formula. Science , this issue p. 1491 ; see also p. 14…
Decomposition studies of group 6 hexacarbonyl complexes. Part 1: Production and decomposition of Mo(CO)6 and W(CO)6
Abstract 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 complex – Sg(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 applying this technique. By in…
The squeezer ion guide
Abstract The properties of an ordinary ion guide can be improved by inserting a grid between the nozzle and the skimmer. When positive ions are transported, an electric potential lower than +10 V is connected to the grid and one of the order of − 10 V to the skimmer. Efficient focusing is achieved between the nozzle and the grid by a combined action of the viscous helium flow field and the weak electric field. The focusing device is called a “squeezer”. It can be extended by adding more grids, a second skimmer, and differential pumping. Contrary to the first grid, the additional elements act more or less like electrostatic lenses in medium vacuum. With the squeezer ion guide, ions created i…
Velocity distribution of ion beams from the RIKEN IGISOL
Abstract A direct measurement of the velocity distribution of ion beams from an ion-guide isotope separator on-line (IGISOL) was carried out at RIKEN with a technique of laser spectroscopy. The skimmer-potential and gas-cell pressure dependence of the velocity distribution were also measured. The velocity distribution was found to be about two times narrower than that estimated from the mass resolving power (MRP). It is pointed out that the velocity spread deduced from MRP is considerably overestimated at various conditions. The way of improvement to make the velocity distribution of the ion beam from the IGISOL narrower and the feasibility of fast atomic-beam collinear laser spectroscopy a…