Journal Article Research Support, Non-U.S. Gov't 0P2197HHHN A-D-A′-D-A type small molecules Aluminum CPD4NFA903 Carbazoles Fluorenes Polymers Quinoxalines carbazole femtosecond transient absorption spectroscopy fluorinated conjugated polymers interchain aggregation inverted polymer solar cells multiple D-A effect organic field-effect transistors organic light-emitting devices organic solar cells short-wavelength infrared side‐chain random copolymer siloxane‐terminated side chain simple backbone sub-gap turn-on voltage