title: Discotic liquid-crystalline materials based on porphycenes: a mesogenic metalloporphycene-tetracyanoquinodimethane (TCNQ) adduct.
abstract: A number of substituted zinc(II) porphycenes and porphyrins have been synthesized as potentially mesogenic materials. One of the resulting porphycenes, bearing eight decyloxy chains, exhibits two mesophases, a transient lamellar phase (Lam) and a highly ordered lamello-columnar phase (L(Col)), with remarkably different structural characteristics. The same zinc(II) porphycene also forms an electron donor-acceptor (EDA) complex with tetracyanoquinodimethane (TCNQ), generating a hexagonal columnar mesophase (Col(h)) that is thermally stable up to ca. 200 degrees C. The EDA interaction between porphycene and TCNQ has been probed using electronic and vibrational spectroscopy. A mixture of zinc(II) porphyrins, isomeric with the above porphycene complex, forms a rectangular columnar mesophase (Col(r)).
authors.affiliation: Department of Chemistry & Biochemistry, University of Texas, 1 University Station A5300, Austin, TX 78712, USA.
authors.forename: Marcin
authors.initials: M
authors.lastname: Stepień
authors.forename: Bertrand
authors.initials: B
authors.lastname: Donnio
authors.forename: Jonathan L
authors.initials: JL
authors.lastname: Sessler