1. not involving or producing electromagnetic radiation or energy emission
Usage: physics; chemistry

Examples

• The radiationless transition allowed the molecule to return to its ground state without emitting light.
• Scientists studied the radiationless decay process in the excited atoms.
• The radiationless relaxation pathway was more efficient than photon emission.
• Radiationless processes can compete with fluorescence in certain materials.
• The researcher measured both radiative and radiationless transition rates.
• Internal conversion is a common radiationless deactivation mechanism.