Photophysical properties of 6 and 7 derivatives in methanol.

Compound	λ Abs (nm)	E Abs (eV)	ε (104 M−1 cm−1)	λ Em (λEx) (nm)	E em (eV)	SS (nm)	SS (eV)
6a	391	3.17	3.28	519 (416)	2.39	128	0.78
6b	399	3.11	3.32	463 (363)	2.68	64	0.43
6c	398	3.12	4.26	463 (363)	2.68	65	0.44
6d	372	3.33	2.79	505 (340)	2.46	133	0.88
7a	390	3.18	3.27	467 (413)	2.66	77	0.52
7b	398	3.12	3.37	466 (398)	2.66	68	0.45
7c	398	3.12	4.26	566 (395)	2.19	168	0.92
7d	372	3.33	2.79	467 (393)	2.66	95	0.68