I haven’t had time to look at it closely, but a paper showed up on the physics arXiv claiming possible discovery of element 122. They were analyzing thorium-containing solutions in an inductively-coupled plasma sector field mass spec (ICP-SFMS) and saw a peak they could not explain at mass 292. They argue this should be from an element with atomic number 122. They cite an abundance relative to thorium of about 1E-12. My early, somewhat uninformed, guess is that a contaminant is responsible, but it should make for an interesting read.

PDF Article Link

The discovery of a new isotope of Bohrium, by Nelson et al., was published yesterday in PRL. In total, 8 events of ²⁶⁰Bh were reported. Unfortunately, the new isotope is not long-lived enough to be of practical chemical interest. A summary of the decay properties is summarized in the Nuclear Trading Card format shown below.

The yellow color signifies the observation that it decays by alpha emission 100% of the time. Fortunately the nuclide decays into ²⁵⁶Db, which is long-lived enough for chemistry, and the results taken with this paper and others updates the known decay properties of Dubnium-256. The updated trading card is below.

In this case the red signifies an ~30% electron capture branch. We hope you enjoy the announcement of a new member to the Bohrium family, and have fun with your new nuclear trading card.

Note 1: Link to article: Lightest Isotope of Bh Produced via the ²⁰⁹Bi(⁵²Cr, n)²⁶⁰Bh Reaction

Mitch

Baumann et al. have recently reported the discovery of three new isotopes ⁴⁰Mg, ⁴²Al, and ⁴³Al. The discovery is notable for producing an isotope that neither the finite range droplet model (FRDM) nor the Hartree-Fock-Bogoliubov (HFB-8) predicted should be bound.

Of the 3 isotopes, the discovery of ⁴²Al is an unexpected surprise and thusly the most fascinating. As we all know from undergraduate nuclear chemistry the Weizsäcker’s formula contains a pairing term (d) approximately equal to 34*A^-3/4 MeV. The term increases the binding energy for an even number of protons (Z) and neutrons (N), decreases it for an odd Z and N, and of course is zero for an odd atomic number (A). ⁴²Al contains 13-protons and 29-neutrons, lies on the extreme neutron-rich side, and thus was not predicted to exist in a bound state.

Theory can be seen to be in contradiction from experimental data as seen below.

Reprinted by permission from Macmillan Publishers Ltd: Nature 449, 1022 - 1024 (25 Oct 2007).

To the immediate left of the ⁴³Al dot is the collection of ⁴²Al events. The ⁴³Al event had a probability of ~2 x 10^-3 of arising from the Al-42 cluster of events.

The tantalizing conclusion of this work is that the neutron-drip line may reside further than even the next generation nuclear facilities could explore for Z>12.

Link to article: http://dx.doi.org/10.1038/nature06213

Mitch