excimer

[ ek-suh-mer ]

noun

, Chemistry.

1. a molecular complex of two, usually identical, molecules that is stable only when one of them is in an excited state.

excimer

/ ˈɛkˌsaɪmə /

noun

1. physics an excited dimer formed by the association of excited and unexcited molecules, which would remain dissociated in the ground state

Word History and Origins

Origin of excimer¹

First recorded in 1960–65; exci(ted) + (di)mer

Example Sentences

Another set of doughnuts revealed the presence of vortex beams of helium excimers, molecules created when a helium atom in an excited, or energized, state pairs up with another helium atom.

From Science News