atomic energy vs nuclear energy

atomic energy and nuclear energy both are nouns.

Word	Noun	Adjective	Verb	Adverb
atomic energy	Yes	No	No	No
nuclear energy	Yes	No	No	No

As nouns, atomic energy and nuclear energy are synonyms defined as:

atomic energy and nuclear energy: the energy released by a nuclear reaction

atomic energy (noun)	nuclear energy (noun)
the energy released by a nuclear reaction	the energy released by a nuclear reaction