selection rule

noun

: 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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Cite this Entry

“Selection rule.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/selection%20rule. Accessed 19 Mar. 2024.

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