Uranium ground state electronic configuration

Nobelium is a member of the actinide series of elements. The ground state electron configuration is assumed to be (Rn)5fl47s2, by analogy with the equivalent lanthanide element ytterbium ([Kr]4fl46s2) there has never been enough nobelium made to experimentally verify the electronic configuration. Unlike the other actinide elements and the lanthanide elements, nobelium is most stable in solution as the dipositive cation No ". Consequently its chemistry resembles that of the much less chemically stable dipositive lanthanide cations or the common chemistry of the alkaline earth elements. When oxidized to No, nobelium follows the well-estabhshed chemistry of the stable, tripositive rare earth elements and of the other tripositive actinide elements (e.g., americium and curium), see also Actinium Berkelium Einsteinium Fermium Lawrencium Mendele-vium Neptunium Plutonium Protactinium Ruthereordium Thorium Uranium. 

Radon, Rn At. no. 86, at. wt 222, mp—71°C, bp -61.8°C. Radon is an intermediate radioactive decay product of Ra. Rn, the most stable isotope of radon, is obtained as a gas from aqueous solutions of RaCl2 and has been used as a radiation source and as a gaseous tracer. It is a considerable hazard in uranium mines. In some areas, radon in basements and in ground water is a potential health hazard because of its radioactivity. The ground state electronic configuration of radon is [Xe]4f " 5d °6s 6p. Because radon is intensely radioactive, the chemistry of radon has only been investigated on the tracer scale. Radon forms compounds, particularly a fluoride (likely RnF2), and solid adducts between the fluoride and Lewis acid fluorides. 

Ground-state configuration and electronic structure of the monomeric uranium(III) alkyl [t 5-(CH3)5C5]2UCF[[Si(CF[3)3]2 were investigated and reported... 

The alkali metals - lithium, sodium, potassium, rubidium, caesium and francium - are members of group 1 of the periodic table, and each has a ground state valence electronic configuration ns. Discussions of these metals usually neglect the heaviest member of the group, francium. The isotope Fr occurs naturally, but only as the decay product of Ac in uranium ores. The half-life of Fr is 21.8 min, and it is estimated that, at a given moment, there is <30g of francium in the Earth s cmst. Isotopes of Fr can be prepared artificially in nuclear reactions, but have no practical applications. 

Actually, p.e. spectra of open-shell lanthanide elements and complexes show a particular resolution of different orbital states in addition to spin-orbit multiplicities (19). In the case of 5f-element complexes, the open shell systems thus far studied are those related to U(IV) complexes. The pattern of final state structure expected on ionizing one 5f electron from the ground configuration of 5f uranium compounds has been discussed previously [2]. It has been shown that of the 5/2 1/2 states which can be... 

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