gives the value of the specified property for the isotope with atomic number Z and mass number A.


gives the value of the property for the named isotope.


  • Isotope names can be specified by the corresponding element name or abbreviation, followed by a mass number A (e.g. "Sodium23" or "Na23"). The form {"name",A} can also be used.
  • IsotopeData[] gives a list of all known isotopes.
  • IsotopeData[{Z,A}] gives the isotope name.
  • IsotopeData["name"] or IsotopeData[Z] gives a list of all known isotopes of the element with the specified name or atomic number.
  • IsotopeData[{Z,A}] gives Missing["Unknown"] when no isotope with the specified Z, A is known.
  • IsotopeData["Properties"] gives a list of all properties available for the isotopes.
  • Properties that do not apply or are not known in a particular case are indicated by Missing[].
  • Numerical values that are known only to a certain precision are typically tagged with their precision, and given in arbitrary-precision form.
  • Basic isotope properties include:
  • "AtomicMass"mass of isotope in atomic mass units
    "AtomicNumber"atomic number
    "BindingEnergy"binding energy
    "IsotopeAbundance"relative isotope abundance
    "MassExcess"mass excess
    "MassNumber"mass number
    "NeutronNumber"number of neutrons
    "QuantumStatistics" for bosons, for fermions
  • Quantum number and structural properties include:
  • "MagneticMoment"magnetic moment in nuclear magnetons
    "QuadrupoleMoment"electric quadrupole moment in barns
  • Decay-related properties include:
  • "BranchingRatios"branching ratio of each decay mode
    "DaughterNuclides"final daughter nuclide of each mode
    "DecayEnergies"decay energy of each mode in keV
    "DecayModes"list of observed decay modes
    "DecayModeSymbols"standard symbols for observed decay modes
    "DecayProducts"list of all final decay products and branching ratios
    "HalfLife"decay half-life in seconds
    "Lifetime"decay lifetime in seconds
    "MolarRadioactivity"radioactivity per mole
    "SpecificRadioactivity"specific radioactivity
    "Stable"whether the isotope is stable
    "Width"decay width in MeV
  • Examples of decay mode designations include: "AlphaDecay", "BetaDecay", "BetaPlusDecay", "ProtonEmission", "NeutronEmission", "SpontaneousFission", and "ElectronCapture". "Delayed" decay mode designations indicate the presence of an intermediate excited state.
  • Ordinary decay-related properties include only final ground-state decay products.
  • Properties of excited states include:
  • "ExcitedStateEnergies"list of energies in keV
    "ExcitedStateHalfLives"list of decay half-lives in seconds
    "ExcitedStateLifetimes"list of decay lifetimes in seconds
    "ExcitedStateParities"list of parities
    "ExcitedStateSpins"list of spins
    "ExcitedStateWidths"list of decay widths in MeV
  • Names-related properties include:
  • "FullSymbol"full abbreviation
    "Name"English name (e.g. "helium 4")
    "StandardName"standard Wolfram Language name (e.g. "Hydrogen3")
    "Symbol"standard abbreviation
  • IsotopeData["class"] gives a list of isotopes in the specified class. IsotopeData[name,"class"] gives True or False depending on whether the element corresponding to name is in the specified class.
  • Classes of isotopes include:
  • "AlphaDecay"decays via decay
    "BetaDecay"decays via decay
    "BetaPlusDecay"decays via decay
    "Boson"obeys BoseEinstein quantum statistics
    "ElectronCapture"decays via electron capture
    "Fermion"obeys FermiDirac quantum statistics
    "NeutronEmission"decays via neutron emission
    "ProtonEmission"decays via proton emission
    "SpontaneousFission"decays via spontaneous fission
    "Stable"stable with respect to radioactive decay
    "Unstable"unstable with respect to radioactive decay
  • IsotopeData["name","property","ann"] gives various annotations associated with a property. Typical annotations include:
  • "Description"short textual description of the property
    "Interval"uncertainty range given by Interval[]
    "LongDescription"longer textual description of the property
    "Note"additional information about the property
    "Units"units in which the value is given
    "UnitsName"English name for the units used
    "UnitsNotation"notation for the units used
    "UnitsStandardName"Wolfram Language standard name for the units used
    "Value"property value (default if no annotation is specified)


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Basic Examples  (4)

Find the atomic mass of uranium-235:

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Find the magnetic moment of tritium:

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Find the decay modes of lead-181:

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Plot the excited state energies of oxygen-15:

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Scope  (17)

Generalizations & Extensions  (1)

Applications  (5)

Properties & Relations  (8)

Possible Issues  (2)

Neat Examples  (1)

Introduced in 2007
Updated in 2014