Pb206iin
Pb206iin is not a standard designation in current nuclear data. In formal nomenclature, nuclides are written with the element symbol followed by a mass number (for example, Pb-206). The appended letters “iin” do not convey a recognized nuclear property or state and are not used in established tables of nuclides. If encountered, the string is most likely a transcription error, an internal dataset tag, or a fictional/fictionalized label rather than a real isotope.
Lead has four stable isotopes in nature: Pb-204, Pb-206, Pb-207, and Pb-208. Pb-206 is the second most
In nuclear spectroscopy, some nuclides have metastable excited states, denoted with an “m” (for example, 206Pb-206m).
For authoritative information on lead isotopes and their properties, refer to standard nuclear data compilations and