Do Chemists "discover," "invent," or "create" things?
discover
invent
create
innovate


Create is totally weird with chemistry, you can create item, but substance?

Innovate is more about improving something existing.

This leaves us with discover and invent, which in case of chemistry seems to me almost equivalent. For "invent" I would imagine targeted effort towards a new substance with desired properties, whereas "discover" evokes more trial-and-error approach.