Positive Magneto-LC Effect in Conjugated Spin-Bearing Hexabenzocoronene

Abstract

The first neutral spin carrying hexabenzocoronene (HBC) derivative is described. The conjugated phenyl nitroxide substituted HBC with five alkyl chains exhibits a positive magneto-LC effect in columnar hexagonal liquid crystalline phase as probed by differential scanning calorimetry and electron paramagnetic resonance spectroscopy. Surprisingly, at 140 K the Δ<i>M</i>_S = 2 transition can be observed indicating a thermally accessible triplet state between the neighboring molecules in the columnar arrangements