Ground state properties. The absorption spectra of the AL(DIPY)3 complexes are displayed in Figure . For clarity the spectra were grouped and distributed in three graphs as their features are overlapping. All complexes displayed two pronounced characteristic bands at ca. 450 and 500 nm (Table ). Lower values of molar absorption coefficient (ε at 450 nm band) ranged from ~40,000 to ~60,000 cm -1 M -1 for 13a, 13j, 16, 17, and 18; whilst for 13c, 13f, 13h and 13i ε was two times higher (range of ~90,000 to ~140,000 cm -1 M -1 ). The BODIPY-AL(DIPY)3 conjugate 20 displayed the highest absorptivity ~ 250,000 cm -1 M - 1 at 500 nm due to the strong absorbance of the BODIPY moiety. The difference between the absorption spectra of the single dipyrrin chromophores (Fig. ) and the AL(DIPY)3 complexes is apparent, with the former displaying a broader single band at ~430 nm with lower molar absorption coefficient and the latter displaying a double, red-shifted band (Fig. ).