Yes, by all means and it's illustrated by the unbelief of the jews who departed from egypt Heb 3:16-19. Now notice vs 17 " them that had sinned" are them that believed not in vs 18-19, the sin was believing not or unbelief.
So now when Paul preached that Christ died for our sins 1 Cor 15:3, and yet that didn't include their sin of unbelief, then he lied on Christ. The point is this, if Christ died for our sins, then He died for our unbelief, and we can't be condemned for it as some are Jn 3:18.
Now now proof positive that unbelievers Christ died for can not be condemned for unbelief is Rom 5:10, that while we were enemies and unbelievers obviously, we still had been reconciled to God by the death of His Son, which is not the case if we are under condemnation for unbelief.