forbidden transition


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forbidden transition

[fər¦bid·ən tran′zish·ən]
(quantum mechanics)
A transition between two states of a quantum-mechnical system which is considerably less probable than a competing allowed transition.
References in periodicals archive ?
2 nm light to cause the forbidden transition through Stark and quadrupole (QDP) transitions from 21S atoms to 31D states of HeI.
This instrument enables classroom demonstrations of simple topics, such as free radicals in everyday life, to far less intuitive subjects like electron density, spin-orbit coupling, spin-spin exchange and forbidden transitions.
m = 1/2 and 3/2 corresponds to direct allowed and direct forbidden transitions and m = 2, 3 corresponds to indirect allowed and indirect forbidden transitions, respectively [22].