. 2010 Dec 7;15(12):8915–8932. doi: 10.3390/molecules15128915

Table 1.

Absorption and fluorescence spectra of coumarins 1-8 in chloroform and methanol.

Substrate ^a	chloroform					methanol
Substrate ^a	λ_A ^b nm	Logε^c dm³mol⁻¹ cm⁻¹	λ_F nm	Φ_r(A)^e	τ^f ns	λ_A^b nm	Logε ^c dm^-3mol⁻¹ cm⁻¹	λ_F^d nm	Φ_r(A)^e
1	432	3.98	480	4.27	0.7	440	4.099	475	0.55
2	436	4.40	487	1.91	1.7	436	4.586	505	4.11
3	333	4.21	400	0.18		329	4.331	433	0.14
4	356	4.59	405	0.05		352	4.352	438	0.09
5	350	4.22	426	0.82	2.1	337	4.308	437	0.17
6	356	4.280	425	1.37	1.4	356	4.280	449	0.22
7	440	4.69	474	13.96	2.3	440	4.450	494	0.40
8	338	4.73	403	9.93	3.1	352	4.823	433	3.04

^a Structure of the substrates according to Figure 1; ^b Maximum of the longest wavelength absorption band; ^c Log of the decadic extinction coefficient; ^d Maximum of the emission band;^e Relative quantum yield to anthracene. Approximate absolute quantum yield is obtained by using absolute quantum yield of anthracene 0.2 for methanol and 0.11 for chloroform; ^f Fluorescence lifetime.