“…Given a single maximum, it is still possible to precisely determine film thickness. The theoretical minimum thickness that can be determined unambiguously from the absorbance maximum is D = λ/(4 n 2 ), which for 190 nm is a minimum measurable thickness of water ( n 2 = 1.441) of 33.0 nm . This formula can be derived by solving eq 2 for m = 0.…”