Table 2. Optical Band Gaps of the Terpolymers and Their Respective Copolymers.

D1	D2	Eg (D1–A) [eV]	Eg (D2–A) [eV]	Eg (D1–A–D2–A) [eV]	Δga [eV]
TPT	2T	1.53	1.20	1.37	–0.005
TPT	3T	1.53	1.33	1.43	0.000
TPT	4T	1.53	1.46	1.50	–0.005
TPT	TTTT	1.53	1.35	1.44	0.000
PyTPy	3T	1.73	1.33	1.49	0.040
TEDOTT	3T	1.17	1.33	1.25	0.000
TDTPT	TBTT	1.23	1.19	1.19	0.020

^aΔ_g = [E_g(D1–A) + E_g(D2–A)]/2 – E_g(D1–A–D2–A).