In reply to Axil Axil's message of Mon, 16 Dec 2013 18:01:07 -0500: Hi, [snip] >Nickel-62 is an isotope of nickel having 28 protons and 34 neutrons. > >It is a stable isotope, with the highest binding energy per nucleon of any >known nuclide (8.7945 MeV). > > It is often stated that 56Fe is the "most stable nucleus", but actually >56Fe has the lowest mass per nucleon (not binding energy per nucleon) of >all nuclides. > >The second and third most tightly bound nuclei are those of 58Fe and 56Fe, >with binding energies per nucleon of 8.7922 MeV and 8.7903 MeV, >respectively. > >As noted above, the isotope 56Fe has the lowest mass per nucleon of any >nuclide, 930.412 MeV/c2, followed by 62Ni with 930.417 MeV/c2 and 60Ni with >930.420 MeV/c2. This is not a contradiction because 62Ni has a greater >proportion of neutrons which are more massive than protons. > >If one looks only at the nuclei proper, without including the electron >cloud, 56Fe has again the lowest mass per nucleon (930.175 MeV/c2), >followed by 60Ni (930.181 MeV/c2) and 62Ni (930.187 MeV/c2). > >For example, the ash produce of Rossis reaction was 10% iron. When nickel >is fashioned into iron and helium, binding energy is released. Helium has >relatively far less binding energy than nickel.
The higher the binding energy, the more energy was released upon formation, hence the more must be added to break it apart. It is more difficult to remove a nucleon from 62Ni than from any other isotope. Being at the top of the binding energy curve means that it doesn't "want" to fission. Thus the reaction: 62Ni - 4He => 58Fe COSTS 7 MeV. It doesn't release energy. In order to get Ni to fission one needs to add a lot of mass/energy. This can be in the form of free nucleons that have zero binding energy. E.g. the reaction 1H+1H+62Ni => 60Ni + 4He + 9.879 MeV > >Since nickel 62 is at the top of the heap relative to binding energy, any >transmutation of nickel will be energetically positive be it from fission >or fusion. Note that the "top of the binding energy curve" is actually the bottom of the potential energy valley. Regards, Robin van Spaandonk http://rvanspaa.freehostia.com/project.html
