Preferred Label : atomic spectral lines;
IUPAC definition : Atomic and ionic spectral lines originate from specified electronic transitions between
energy levels of atoms and ions, respectively. In the past it has been common usage
to denote atomic lines as arc lines and ionic lines as spark lines. This usage is
now considered to be incorrect. The correct way to indicate that lines are due to
atomic or ionic transitions is: Element symbol I wavelength e.g. Cu I 324.7 nm; and
Element symbol II wavelength e.g. Cu II 213.6 nm. Similarly for higher states of ionization,
the type of line is represented by III, IV, etc.;
Origin ID : A00502;
See also
Atomic and ionic spectral lines originate from specified electronic transitions between
energy levels of atoms and ions, respectively. In the past it has been common usage
to denote atomic lines as arc lines and ionic lines as spark lines. This usage is
now considered to be incorrect. The correct way to indicate that lines are due to
atomic or ionic transitions is: Element symbol I wavelength e.g. Cu I 324.7 nm; and
Element symbol II wavelength e.g. Cu II 213.6 nm. Similarly for higher states of ionization,
the type of line is represented by III, IV, etc.
