Talk:Isotopes of europium

What theory?

It was: "¹⁵¹Eu was recently found to be unstable to alpha decay with half-life of $5_{-3}^{+11}\times 10^{18}$ yr, in reasonable agreement with theoretical predictions." I have taken the latter part out, because it doesn't say what theory is meant. —Preceding unsigned comment added by Phr en (talk • contribs) 09:02, 29 February 2008 (UTC)

Low Half-life values of OO63Eu144 and OO63Eu140

The reported half-lives do not agree with the half-life trend line of the rest of the 63Eu Europium OO type isotopes.WFPM (talk) 23:42, 21 April 2013 (UTC)

How would ¹⁵³
Eu decay to a much less stable isotope, ¹⁴⁹
Pm?

Because ¹⁴⁹
Pm is way too unstable, so shouldn't ¹⁵³
Eu be stable too? 80.98.179.160 (talk) 07:06, 26 March 2018 (UTC)

This is pretty normal: the obvious example is that ²³⁸U (half-life 4.468 × 10⁹ years) decays to ²³⁴Th (half-life 24.1 days). The important thing is that the system of ¹⁴⁹Pm plus an alpha particle is a lower-energy arrangement of 63 protons and 90 neutrons than a single ¹⁵³Eu nucleus (just look at the binding energies), and so the decay is energetically allowed. Of course, it is kinetically hindered for other reasons. The beta-instability of ¹⁴⁹Pm has nothing to do with it. Double sharp (talk) 07:15, 26 March 2018 (UTC)