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It's All About the Ununpentium
spitefulcrow writes "The New York Times is reporting that elements 113 and 115 have been created by a joint team of Russian and American scientists. The temporary names are ununtrium and ununpentium until the experiment has been duplicated and verified in another lab. According to the article, speculation has been made that 'Rather than being round, nuclei in that region and beyond could contain bubbles and have strange doughnut-like shapes'."
Interesting notion ... I happened to stumble across a reference to this "ununpentium" the other day while satisfying my science fiction curiosities on a site called "AboveTopSecret.com". Apparently, some of the Area 51 conspiracy theorists believe it's used in anti-gravity research... or something like that.
t 115.htm l
Document about ununpentium published in 1999:
http://www.abovetopsecret.com/pages/elemen
Skiers and Riders -- http://www.snowjournal.com
So, based on that knowledge we can say that Element 115 should be very much like Element 83 (Bismuth), which is the most diamagnetic metal, giving it some very interesting properties.
Also, it should be noted that Element 115 should it possess diamagnetism, and all indications are that it should, it will be a much better diamagnetic material than Bismuth.
How the hell was this determined? Particularly the wobbly Uranium nucleus. Is it just a theory based on mathematical predictions, or is it actually based on direct observations like X-ray, neutron or electron diffraction studies?
Yes.
A number of experimental tools are available for nuclear shape determination:
-The electric quadrupole moment
-Neutron scattering experiments
-Giant dipole resonance
-Momentum distributions of collision fragments
In principle the nucleons can be approximated as particles existing in a square potential well, defined by the positions of all the other particles. Solving for a wave function in a potential well like that reveals a set of solutions with associated quantum numbers, which turn out to be somewhate analogous to those calculated for the hydrogen atom with its inverse-square potential, and which we can identify in the energy levels and spectra of real, nonidealized nuclei.
Things are complicated by the fact that the potential within a nucleus is not strictly definable as a potential. It is created by the sum of the nuclear and electromagnetic forces and these fall off at different rates. The nuclear force is short range, but the electromagnetic force reaches all the way across the nucleus. So when they reach a certain size you see the effects of the charge buildup. Large scale movements of particles through the nucleus become evident, and sometimes pieces even break off if merely poked by a slow neutron. Your skepticism is not unreasonable. In fact researchers had a hard time believing their own experiments when they exposed uranium to neutrons and suddenly had to explain the appearance of barium.