Rydberg constant

noun

variants or Rydberg unit

: a wave number characteristic of the atomic spectrum of each element equal to the constant factor in the wave-number formula for all the spectral series of the elements and having a value from 109,678 cm⁻¹ for hydrogen to 109,737 cm⁻¹ for the heaviest elements

Word History

Etymology

after Johannes R. Rydberg

First Known Use

1900, in the meaning defined above

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