uranyl vs uranyl group

uranyl and uranyl group both are nouns.

Word	Noun	Adjective	Verb	Adverb
uranyl	Yes	No	No	No
uranyl group	Yes	No	No	No

As nouns, uranyl and uranyl group are synonyms defined as:

uranyl and uranyl group: the bivalent radical UO2 which forms salts with acids

Other synonyms of uranyl include uranyl radical.

uranyl (noun)	uranyl group (noun)
the bivalent radical UO2 which forms salts with acids	the bivalent radical UO2 which forms salts with acids