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IsotopeData[{Z, A}, "property"]
gives the value of the specified property for the isotope with atomic number Z and mass number A.
IsotopeData["name", "property"]
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["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[...].
  • When not noted otherwise, all relevant quantities are given in SI (MKS) units. IsotopeData["name", "prop"] gives the numerical value; IsotopeData["name", "prop", "Units"] gives the units used.
  • 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 Z
"BindingEnergy"binding energy
"IsotopeAbundance"relative isotope abundance
"MassExcess"mass excess Delta
"MassNumber"mass number A
"NeutronNumber"number of neutrons
"QuantumStatistics"+1 for bosons, -1 for fermions
  • Quantum number and structural properties include:
"MagneticMoment"magnetic moment in nuclear magnetons
"Parity"parity pi
"QuadrupoleMoment"electric quadrupole moment in barns
"Spin"spin J
  • Decay-related properties include:
"BranchingRatios"branching ratio of each decay mode
"DaughterNuclides"final daughter nuclide of each mode
"DecayEnergies"decay energy Q 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 T_(1/2) in seconds
"Lifetime"decay lifetime in seconds
"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. "hydrogen 3")
"StandardName"standard Mathematica 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 alpha decay
"BetaDecay"decays via beta^-decay
"BetaPlusDecay"decays via beta^+decay
"Boson"obeys Bose-Einstein quantum statistics
"ElectronCapture"decays via electron capture
"Fermion"obeys Fermi-Dirac 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"Mathematica standard name for the units used
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