This article presents syntheses, absorption spectra and fluorescence m
easurements of three diapocarotenoids with different chain lengths (7,
9 and 11 conjugated double bonds). These compounds exhibit S2-S0 as we
ll as S1-S0 fluorescence. The feature of total luminescence depends st
rongly on the choice of the solvents and the concentrations of the sol
utes.