Even and odd atomic nuclei abundant isotopes of their element, the former only by a small margin, and the latter only because the expected beryllium-8 has lower binding energy than two alpha particles and therefore immediately alpha decays. Actinides with odd neutron number are generally fissile (with thermal neutrons), while those with even neutron number are generally not, though they are fissionable with fast neutrons. Only , and have odd neutron number and are the most naturally abundant isotope of their element. Even and odd atomic nuclei In nuclear physics, properties of a nucleus depend on evenness or oddness of its atomic number "Z", neutron
Mirror nuclei - 1. Examples of mirror nuclei: Pairs of mirror nuclei have the same spin and parity. If we constrain to odd number of nucleons (A=Z+N) then we find mirror nuclei that differ one another by exchanging a proton by a neutron. Interesting to observe is their binding energy which is mainly due to the strong interaction and also due to Coulomb interaction. Since the strong interaction is invariant to protons and neutrons one can expect these mirror nuclei to have very similar binding energies. Mirror nuclei Mirror nuclei are nuclei where the number of protons of element one (Z) equals