Variation of the Side Chain Branch Position Leads to Vastly Improved Molecular Weight and OPV Performance in 4,8-dialkoxybenzo[1,2-b:4,5-b′]dithiophene/2,1,3-benzothiadiazole Copolymers

Table 2

Summary of optical and electrochemical properties.

	𝜆max (nm)	𝐸^opt𝑔 (eV)	𝐸^oxonset (V)	HOMO (eV)	𝐸^redonset (V)	LUMO (eV)	𝐸^elect𝑔 (eV)
P1	598	1.69	0.15	−4.95	−1.72	−3.08	1.87
P2	579	—	0.13	−4.93	−1.62	−3.18	1.75
P3	637	1.69	0.12	−4.92	−1.59	−3.21	1.71