There are nine different fission Isotopes, nine fusion Isotopes, and one mechanical Isotope in NuclearCraft. They are used mostly for creating various Nuclear Fuels.
Fission Isotopes[]
Thorium-230: Helium Collectors, decays into Lead
Thorium-232: TBU Fuel, Decays into Thorium-230
Uranium-233: LEU-233/HEU-233, Decays into Lead
Uranium-235: LEU-235/HEU-235, Decays into Lead
Uranium-238: Provides the nonreactive part for all MOX and Uranium-based Fuels, Decays to Thorium-230
Plutonium-238: RTG Cells, Decays to Thorium-230
Plutonium-239: LEP-239/HEP-239/MOX-239, Decays to Uranium-235
Plutonium-241: Nukes, LEP-241/HEP-241/MOX-241, Decays into Uranium-233
Plutonium-242: Provide nonreactive part for all Plutonium-based fuels, Decays into Uranium-238
Fusion Isotopes[]
Hydrogen-1 (Hydrogen/Protium): Fusion, Produced by Electrolyser
Hydrogen-2 (Deuterium): Fusion, Produced by Electrolyser
Hydrogen-3 (Tritium): Fusion, Produced by Electrolyser, Decays into Helium-3
Helium-3: Fusion, Produced by decaying Tritium
Helium-4: Entirely useless currently, Produced by many different fusion reactions
Lithium-6:
Lithium-7:
Boron-10:
Boron-11:
Mechanical Isotopes[]
Oxygen: Used in Oxidiser to produce Oxide Nuclear Fuels