The GetIsotopes() command returns an expression sequence containing selected isotopes of elements of the periodic table in the ScientificConstants package.

If the 'element'=elem option is given, only isotopes of the given element elem are returned, where elem can be any valid descriptor of an element.

If any prop_name option(s) are given, only elements with these properties defined are returned.  The prop_name option(s) must be isotopic properties.

If the 'output=symbols' option is given, the isotopes are returned in the form [atomic_number, mass_number].  This is the default.

If the 'output=atomicnumbers' option is given, the isotopes are returned in the form [atomic_number, mass_number].

The sequence of isotopes is ordered first by atomic number, then by mass number.

$\mathrm{with}\left(\mathrm{ScientificConstants}\right)\:$

$\mathrm{GetIsotopes}\left(\mathrm{element}=H\right)$

$H_1,H_2,H_3,H_4,H_5,H_6$

$\mathrm{GetIsotopes}\left(\mathrm{electronaffinityisotopic}\,\mathrm{output}=\mathrm{atomicnumbers}\right)$

$\left[1\,1\right],\left[1\,2\right]$