Semiflexible Star-Shaped Mesogens as Nonconventional Columnar Liquid Crystals

The cyclic voltammograms (CV) of N,Nʹ-bis(propyl)3,4,9,10-perylenebis(dicarboximide) [PTCDIPr] and N,Nʹ-bis(neopentyl)-3,4,9,10-perylenebis (dicarboximide)[BNPTCD] in Langmuir-Blodgett (LB) films, in carbon paste electrode (CPE), and in solution for BNPTCD are reported here for the first time. The data allow a comparison of the electrochemical behavior of highly organized LB films with the results obtained on CPE, where the active molecules are randomly dispersed in a carbonaceous matrix. The electrochemical reduction waves indicate the reversible formation of stable radical anions and dianions. The discussion of reduction potentials is integrated with spectroscopic data and the HOMO-LUMO energy positions of both materials obtained from density functional theory computations