What are nuclear isomers? What is isomeric energy? Can someone explain nuclear isomers to me, and in particular what the energy involved is? I understand generally that we're talking about moving from a less to more stable configuration of nuclear particles, but that's about as far as my understanding goes.
 A: Given that we don't have an answer yet, I'll chime in to say that I've not heard this term before despite being a nuclear physicist in grad school. 


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*Isotopes are atoms with the same number of protons, but different numbers of neutrons. Accordingly they have the same chemical properties, but differing atomic masses. (Actually there is a small difference in some chemical properties such as vapor pressures that can be used to extract enriched isotopic samples, but these differences are small enough that the processes tend to be expensive.)

*Isomers in chemistry are molecules with the same atomic content, but differing structure. The simplest example that comes to mind are the left- and right-handed versions of some large organic molecules.
From that we deduce that if we found some isotope that had two stable configurations we would call them "nuclear isomers" by the obvious extension. Which leads to the speculation that meta-stable nuclear states might be given that name.
Take that with a grain of salt. I've no references and no experience with the term in the mouths of practicing scientists.
A: same atomic number and same mass number but differ in their structure and energy.
