spectroscopic vs spectroscopical

spectroscopic and spectroscopical both are adjectives.

Word	Noun	Adjective	Verb	Adverb
spectroscopic	No	Yes	No	No
spectroscopical	No	Yes	No	No

As adjectives, spectroscopic and spectroscopical are synonyms defined as:

spectroscopic and spectroscopical: of or relating to or involving spectroscopy

spectroscopic (adjective)	spectroscopical (adjective)
of or relating to or involving spectroscopy	of or relating to or involving spectroscopy