Surface-Mediated Recrystallization for Highly Conducting Organic Radical Crystal

Abstract

Electrically conducting cation-charged dihydrophenazinium radical (H 2 PNZ •+ ) crystals were formed by a one-pot photoreaction. Furthermore, new secondary crystals were grown directly from the H 2 PNZ •+ crystal surface through a surface-mediated recrystallization (SMR) process by a secondary photoreaction with water. Depending on the absence or presence of light during the exposure of the H 2 PNZ •+ single crystal to water, neutral yellow PNZ crystals (SMR Y ) or densely packed green H 2 PNZ •+ crystals (SMR G ) were formed, respectively, on the surface of the mother H 2 PNZ •+ crystal. The single-crystal X-ray analysis reveals that the newly obtained SMR G radical crystal exhibits a shorter intercolumnar distance than the original H 2 PNZ •+ crystal, resulting in increased electrical conductivity. Copyright © 2019 American Chemical Society