Rydberg, Johannes Robert (1854–1919)
Swedish chemist who classified optical spectra and developed
(1890) empirical formulae for spectral lines,
using a constant (1.097 × 107 m-1) now known
as the Rydberg's constant (symbol R). He also
studied hydrogen line wavelengths (see hydrogen
spectrum). The Rydberg atom is a highly excited hydrogen
atom that exhibits chaotic behavior in a strong magnetic field.