Optical and electronic properties of polymers P15–17 prepared via cyclopentannulation. The absorption onset wavelengths (λ_onset) were determined measuring thin films of the polymers and converted to give the optical band gaps (E_g (opt.)). E_ox1,onset and E_red1,onset were obtained from CV measurements using polymer thin films (in 0.1 M nBu₄NPF₆ in CH₃CN).

Polymer	λ onset (nm)	E g (opt.) (eV)	E ox1,onset (V vs. Fc/Fc+)	E red1,onset (V vs. Fc/Fc+)	Δ|Eox1,onset−Ered1,onset| (eV)	HOMO (eV)	LUMO (eV)
P15	817	1.52	0.70	−1.37	2.07	−5.50	−3.43
P16	821	1.51	0.64	−1.39	2.03	−5.44	−3.41
P17	824	1.50	0.61	−1.42	2.03	−5.41	−3.38