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Ritz combination principle

American  
[rits] / rɪts /

noun

Physics.
  1. the principle that the frequencies of lines in atomic spectra can be represented as differences of a smaller number of terms, all characteristic of the emitting system, interpreted in quantum theory as the emission of exactly one photon in a transition between energy levels.


Etymology

Origin of Ritz combination principle

After Walther Ritz (1878–1909), Swiss physicist, who formulated it