Npe:TCNQ co-crystals were synthesized by dissolution; 0.15 mmol of Npe and 0.1 mmol of TCNQ were combined in a 7 mL vial with 4 mL of MeCN and heated/boiled until all solids were dissolved, resulting in a dark green solution that forms small blue-like plates as it slowly cools to room-temperature overnight. (Note: the crystallographic ratio is the opposite of the synthesis conditions). Further purification and isolation were achieved by washing with cold MeCN. Elemental Analysis of 2Npe:3TCNQ co-crystal: C17 H13 N,1.5(C12 H4 N4). Calculated: C 78.20, H 3.56, N 18.24; Found: C 77.30, H 3.22, N 17.84.