 Second, MCD will be found where no absorption is detected at all if ΔA > (ΔAmin) but Amin, where (ΔA)min and Amin are the minimum of ΔA and A that are detectable.Typically, (ΔAmin) and Amin are of the magnitudes around 10−5 and 10−3 respectively.So, a transition can only be detected in MCD, not in the absorption spectroscopy, if ΔA/A > 10−2.