Atomic energy yields diamonds (3)
I believe the answer is:
ice
'diamonds' is the definition.
(slang term for diamonds)
'atomic energy' is the wordplay.
'ICE' is hidden within the letters.
However, I'm not sure how this is indicated.
'yields' acts as a link.
Can you help me to learn more?
(Other definitions for ice that I've seen before include "Cubes in a drink" , "Cold stuff used in enticement" , "such an age" , "Solid water" , "Top cake" .)