selection rule


: a rule that states which of all the conceivable changes in the state of a quantized system (atoms, nuclei, or related entities) are physically possible under specified circumstances usually in terms of the possible numerical changes in the quantum numbers that characterize the system compare allowed, forbidden

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Dictionary Entries Near selection rule

Cite this Entry

“Selection rule.” Dictionary, Merriam-Webster, Accessed 7 Jun. 2023.

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