national capital vs capital of Austria

national capital and capital of Austria both are nouns.

Word	Noun	Adjective	Verb	Adverb
national capital	Yes	No	No	No
capital of Austria	Yes	No	No	No

national capital (noun)	capital of Austria (noun)
the capital city of a nation	the capital and largest city of Austria; located on the Danube in northeastern Austria; was the home of Beethoven and Brahms and Haydn and Mozart and Schubert and Strauss